I just do not understand why I make such obious blunders. In the opening everything went well and then...

You got to make a habit out of applying proper thought process regime on EVERY move. First: "If it were his turn, what would be ALL his checks, captures and threats?" And when you consider a candidate move: "If I would make THAT move, what would then be ALL his checks, captures and threats?" 

Once you do that routinely, these obvious blunders will disappear.

Would it be fair to say, that when you played Re8+, you were not looking at the bishop on d7 (in spite of it being so close to e8) ?

Answer that question and you have a strategy for progress.

Thanks

use chess program to help you just like my opponents do ... chess.com is a shit , there's not any protection from cheaters . gtfu u ruined it

I was only looking at the check

yes, but I want to play chess and not just win...

Don't feel too bad - it happens. This was a live game, and I find sometimes in live I can get so focussed on my own plan (ie tunnel vision) that I completely ignore the obvious counters and threats to me. I think the suggestion from Bubatz above is good. Basically take the time to have a deep breath and think about the big picture before you commit your move.

That is what it is. I usually have my hand on my piece ready to move.

There's your answer to your original question. You placed your rook on a protected square.

No need to push for an early mate via a risky bishop sacrifice when you're a rook up. Just exchange down and win.

13. Qg8 creating a mate square on f7, btw, after which he's buggered.

 I am going to make a conservative guess that the above accounts for about 80% of my losses.

And by this I mean I do a good analysis for almost all the moves of the game, but then there is always one little move where I get lazy and say "I dont need to overthink this one, its obvious." But, of course, it isnt.

Instead of 12.Rd1 I really like Bh6, it increases pressure on the pinned knight and connects your rooks, you could then follow with Re1, Rd1 type moves afterwards and he still has several moves to get a bit of relief with a queenside castle.

9. e6 looks nice and ugly.

That's what I was thinking, too.  I also had a gut feeling you (the OP) were going to get hosed when you attacked the 0-0-0 king with your queen with so little support.  You'll notice your queen commanded very few squares after that and was penned in with little help.  Consider a pawn storm with your queenside pawns as an attack on 0-0-0.

That said, as others have mentioned, your tunnel vision proved to be the hara kiri.  Work on owl eyes, and you'll convert those early advantages.  :)

What's wrong with you is that you're human, so you make mistakes. But Bubatz's comment is very much on point, and by following his advice you will make fewer errors and also take advantage of more of your opponent's errors. With practice, this kind of checking becomes almost instinctive, but in the beginning you have consciously follow a kind of formal protocol.  When it's your turn to move, I would recommend the following steps: (1) What are the threats? Look at your opponents position after he moved and ask yourself, "if it were his move right now, what could he do to me?" Look at his every check and capture. Is he threatening something? Do you need to defend against that threat? Or can you counter with a more serious threat of your own? If you find that you must respond to his threat in some way, then do it. (2) If you don't have to answer any immediate threat, look at all your checks, captures, and threats. Don't ignore any! See if he can meet them. If not, then you have a tactical advantage, so play your threat. (3) If you don't have a tactic, look at ways to improve your position, but in any case (4) before you move, make the move in your head and try and figure out, "Is it safe?" This last check before moving will save you a lot of points!

I hate it when I get excited and do that. I also hate it when I analyze a position and realize a move that looked good is actually aweful. Then as I spend time calculating another senario or two, I will have forgotten that one move was actually bad. I usually don't remember it again, until after I move....and then I want to go find my own private wall and hang my self stress relief kit.......

it may  help to flip the board to see the game through your oppents eyes and what he,s up 2

By the way, I didn't notice if anyone pointed out that you missed the chance for a big advantage at move 8. When Black played 7...g6, he left his Nf6 with no pawn protection. 8.Bg5 would have pinned the knight, which is now attacked twice. He can try to defend with 8....Bg7, but then 9.e5 dxe5 10.Qxd8+ Kxd8 11.O-O-O+ Ke8 12.Nb5 leaves Black in desperate straits. In the game, Black could have limited the damage with 8....c5, although you are certainly better.

After 10.Qxh8+ your comment: "advantage to me," is a bit of an understatement, isn't it! And don't you think 13.Qg8 would have ended the game? I don't see how he defends against mate accept by something horrible like 13..Be6 14.RxQ8+ or 13...Qb8 14.Qxf7+ Kd8 15.Bg5 I'm sure he would resign instead

How about 22.Qa3 with a deadly pin?

I suspect that you didn't first make the move 24.Re8+ in your head and then ask yourself, "Is it safe?"

I agree with  'by p-worry'. Flip the board and think what would be the move your opponent would LEAST LIKE YOU TO MAKE! That way you will make fewer blunders.