Yeah, I have a hard time with visualization and spatial relations. At the moment I've hit a busy phase in my life, but I will be sure to revisit all of this later when I have time. Thanks again!
Any videos even simpler than John Bartholomew's videos?

@daybreak57 thank you very much for sharing in great detail. one really stupid question, but what happens if/when black safely occupies d5? is there a masters game or reference game to show how that leads to an overwhelming win? i do recognize it's a great center control and leads the way for your pieces to attack down middle or to their weak side....but wasnt sure if there was more to it?
@giasira will check your road to 1600 out...i really enjoy those series. i saw it had 126 posts so wasnt sure i wanted to try and read it before, but now I know i do. i'll also start on the chessnetwork video series. i try and catch jerry playing on twitch or chess and he's amazing. so casual and explains his thinking process so clearly and naturally. hate how he makes it seem so logical and easy haha.
I didn't say black usually gets an overwhelming win when he can get a chance to play d5. I said black has a chance to equalize the game when he can play d5. That is a big difference. Other factors need to exist to be able to lead to a win in order for black to get an "overwhelming victory."
Here is a game I played as black with the Italian. There is not much commentary, but most of the moves are self-explanatory. Play d5 was just the ice-ing on the cake in this game because I was able to win a few pawns that gave me a decisive advantage in the endgame due to blunders my opponent made. I show my blunders as well, and this illustrates that usually at this level even there are blunders on both side of the board.
This game I should have won, and this illustrates the idea again that play d5 is not the ends all beats all in the black side of the Italian game.
This is a game I played as white and lost because my opponent created a weakness on my kingside pawnside and exploited it after I let him! I blundered a lot, but this is an example that black doesn't have to play d5. I'm not going to comment on this game.
I'm going to show you some games in the Fried Liver type spirit. I was playing white in this game and lost.
Here is a master game where black won against the Fried Liver
This is one master game in the Italian. Black plays d6 instead of d5. Again Further Illustrates my new point, that you don't have to play d5 to really win, however, playing d5 can help to ensure an equal game.
In a nutshell. You don't have to play d5 to win a black, though, in my opinion, if black can play d5, it ensures an equal game. Perhaps the reason why these masters who didn't play d5 know that the game might be drawish after d5, or perhaps not. Anyway, don't get what I was trying to say wrong. I'm not trying to say black must play d5. I'm just merely saying that could be one factor in blacks favor to ensure an equal game, and it doesn't even ensure an equal game, things can happen later on... Nothing in chess is 100%.
You don't have to play d5, d6 is another solid move to play at times, as Illustrated. However, it is usually a good idea to play for pawn breaks. That's what I usually do. As white I don't play d3 I play d4 usually. That's my style. Perhaps why I chose to try and always play d5 as black in the games I play against lower-rated players at Starbucks is because I do like to play open and dynamic games. Perhaps it is just in my style. You don't have to play d5, that is just one option.

Learning how to not blunder isn`t a matter of using some special tricks or mental techniques, it comes from habit. I`m rated 1520 in rapid and at my level people (including me) still blunder just due to inattention. It`s only at far higher levels, let`s say 1900+ that pure inattention blunders start to almost completely go away. In blitz they never go away. there are many videos where IM John Bartholomew plays blitz and blunders something in difficult positions or when in time trouble.
In order to build a defense against blundering ,start practicing good chess habits. Always look at the whole board. After every move. You don`t need to try to calculate ahead, just realize what squares are under attack. This will save you from dropping undefended pieces to long-range pieces like a bishop or a rook on the other side of the board for example. Keep an eye on your pieces, ESPECIALLY those that are undefended and/or in your opponents half of the board. If possible you want to always keep everything defended, all through the opening and the middle game. If your opponent moves pieces into your half of the board, you should look for ways to challenge it ASAP even if it`s not immediately attacking something. One piece (except for the queen) often isn`t enough to do any considerable damage to your position, but two pieces infiltrated into your position is often decisive. Don`t let your opponent get there easily.
2. Apart from that , you want to especially pay close attention to the location of your king, queen and rooks. The majority of tactics and major threats target these pieces, so keeping them out of harms way is essential. Are they on the same diagonal, file or rank? If they are there is a possibility that they can be skewered, pinned, or forked. So be on the lookout for that. Again you don`t need to calculate ahead, just ask yourself questions like "if i place my queen/king/rook here, can my opponent attack it next turn? Do I have a response to that attack?" That`s it.
3. Never play moves instantly, no matter how good they may look. If it`s your move and you have a good move to play, such as capturing a piece or a pawn, you should ALWAYS have a very good look around before you play it. Keep a mindset that it is better to lose on time than to play a stupid blunder. This is a turn based game, you`re not in a hurry.
4. Don`t play checks or attacking moves without a follow-up. This is related to the principle of keeping undefended pieces to a minimum. If you start attacking and checking without a clear follow-up threat, you are in danger of leaving a bunch of far-flung pieces around which can be attacked and kicked around while your opponent improves his position. If you play a check or an attacking move, calculate at least one move beyond that move and force yourself to give a reason for the move you`re about to play.
I agree that learning not to blunder doesn't come from learning special tricks, it comes from habit, however, at the start of just beginning, one must constantly check to see if his moves are safe, and check for the threats captures and threats of the position if there are any on both sides, in order to "build" the "habit" of looking for those things. Eventually, looking for those things will become second nature.
In one of your examples, you stated, "You used to spend a long time thinking about where to place your knights." Here is the answer, normally, the knights belong on f3 and c3, those are the best places for the knight, however, sometimes it's better to place them on other squares, only the position will be able to tell you where to place your knights, and reading the position comes with practice.
Those are good types, but things like piece activity and central control I don't believe are the only things one must learn to become a better chess player, even at the beginning. I still think he should when he can watch the JB videos, and go through Logical chess Move by move, and at least consider some of the other advice he has been given in this thread not only by me but by other people as well.
I don't usually give your type of advice because bacon covered that a long time ago, though, it seems, that the page has been taken down for some reason.

Understood. I want to thank both of you, Gisara and Daybreak57, for your comprehensive advice on this. I hope I haven't come off as obstinate or ungrateful. I will be revisiting it before I really sit down again for more chess. (At the moment, due to a hectic schedule, if I played I'd probably just be tired and revert to my old habits immediately.)
I particularly appreciate the more concrete advice and particularly "curriculum" such as videos and mental exercises. Specific instructions really help me in my experience, not just in chess but in life in general.

One last thing before I stop. I will show you two master games where black won and did not play d5. After reviewing these games, and thinking about the types of games played by my opponents at Starbucks, I have come to the conclusion, that, most of the time, black does not get a chance to play d5 in most normal games in the e4 e5 openings. It's just the way these people I play at Starbucks play, they let me. Which reiterates my point, when people "let you" play d5, play it. But if you can't, then you can't. If you can, don't even jump on it because you don't really need to play d5 to equalize the position it seems, but it helps.
One more thing before I post the two master games:
Enjoy the games!

Understood. I want to thank both of you, Gisara and Daybreak57, for your comprehensive advice on this. I hope I haven't come off as obstinate or ungrateful. I will be revisiting it before I really sit down again for more chess. (At the moment, due to a hectic schedule, if I played I'd probably just be tired and revert to my old habits immediately.)
I particularly appreciate the more concrete advice and particularly "curriculum" such as videos and mental exercises. Specific instructions really help me in my experience, not just in chess but in life in general.
No problem just trying to help. You will probably be better than me in a couple of months.

Agree, thank you @Daybreak57 and @Giasira. this is going to be my weekend study from skimming quickly these are definitely applicable lessons to the games I run into and maybe can break my losing streak in rapid hah.
Hopefully, the extra too games won't be too much added to your study... Anyway, go through what you can. I enjoy answering questions. You will probably be better than me in a couple of months if you listen to everything said here.

Well, I know I said that was all I was going to post, but I find this to be incomplete. I never explained why I said in e4 e5 openings black is trying to equalize the game by trying to play "d5." The reason why I said that, is two-fold. One, because like I said, most of the guys at Starbucks, who are much lower rate than I, the play opens like e4 e5 Nc6 d3 as white, allowing me to later build up a strong pawn center by later playing d5.
The other reason why I said this was because I know in the Sicilian, black is usually trying to play d5, which is why a lot of people will try and play a Maroczy Bind.
To Illustrate how playing d5 in the Sicilian as black can help I will show you a game where I played it, however, it didn't really help per say, but remember what I said sometimes it just helps a little and one needs other factors to try and win the game, that alone won't win you the game, or sometimes even might not give you the equality.
Even in the Sicilian, playing d5 really isn't the end of or be all for black. Usually, it's good to play d5, but you see when I played it here I lost the pawn I gained from my opponents opening blunder, and only won the game because my opponent blundered a piece later on.
In this game, I played d5 right off the bat. Playing d5 here didn't automatically win me the game, but it did allow me to eventually have a passed pawn that later won me the game.
There you go. Playing d5 in the Sicilian as black is usually a positional plus, but it isn't needed, d6 is still a viable move to play, and it only helps a little to win, and is never the deciding factor.

Wow. Really good advice by everyone. I would say, just follow it. The only thing I might add is that blindfold visualization does not come till you reach 1800. Some 1700's begin to have it, but not in the See All Variations mode. So if you cannot see all of any annotator's lines, do not be concerned. Visualizing is not that important, especially at your level.
That said, one reason(not the only one) that beginners blunder is no visualizing. That means if you practiced just knowing where your pieces are and your opponent's move to move that you would see a big leap in your ability to win. Why? because while you would know where your pieces are and your opponent's, your opponent would forget that he had a piece on your side that you could trap, winning material.

@Daybreak57 Is Ne3 an option to triple fork after 21 Kg2...? or you have the same effect in the end a rook for a minor piece.
I couldn't really remember the actual game so I made something like a game I would play against him up. I did it fast and didn't see the fork but I did say there was a blunder at the end of the game I didn't explain, that was it. Yes, there was a fork, and yes, he could have saved his queen and avoided mate by not blundering away the game I should have done the fork. I missed it while doing this game fast. I will post another game that I believe I can remember. It is a game we actually played at Starbucks. This one is easy to remember because the whole entire game is based on a single theme.

I just logged on in the first time in a while, saw that this thread continued without me, wasn't sure if I should reply, and will do so for good measure.
I've since kind of given up on chess - the more I tried to improve, the less I enjoyed it I stopped seeing chess as fun entirely. Don't get me wrong, I immensely appreciated (and still appreciate) all the help and advice everyone offered me along the way, but the game just isn't a good fit for my particular mental strengths and challenges. And also, if my threads still somehow continue to help other people who find themselves in similar situations, I am delighted.
Take care everyone!
I would suggest you try one of these https://www.chessable.com/the-fundamentals-build-up-your-chess-1/course/19145/, they are interactive video guides that you might find quite useful.
http://www.qualitychess.co.uk/ebooks/Build-up-Your-Chess-1-exceprt.pdf