why do I suck

(I deleted my comment since I'm unfamiliar with this forum, and it looks like only GMs are supposed to respond.)
mr_hellie_hansen after computer analyzing this game i found your oppent played very strong it wouldnt be a stretch saying this game was played at master level by your oppnent depending on the time control

You played very good, stable, solid, strong. No blunders, no mistakes, just few inaccuracy here and there which is excellent. You know basic stuff, good understanding of endgame. Good game. You opponent made mistakes and you too advantage over them like 28....exf4.

After white played 19.b3, moving your queen to b4 would've been strong. Then white is stuck with a backward and cramped c2 pawn, and black can pile up a battery on the c file, or take advantage of the protected c3 outpost.
Watch out for pawn weaknesses, too. 28... exf4 isolated your d-pawn, leaving it unprotected and alone. In a pawn and rook endgame, every pawn matters. Don't strand them if you can help it.
Other than those two things, I'd say you played pretty well.

Wait what , he is with black pieces? oops.. Well yeah 28.exf4 cost you the game. I think your opponent played very strong for his rating, so dont be dissapointed.
Wait what , he is with black pieces? oops.. Well yeah 28.exf4 cost you the game. I think your opponent played very strong for his rating, so dont be dissapointed.
lol
[Date "03/20/2016 12:43PM"]
[White "mr_hellie_hansen (1562)"]
[Black "lamborghotti (1534)"]
1.e4 e6 2.d4 d5 3.e5 c5 4.c3 Nc6 5.Nf3 Nh6 6.Bb5 Bd7 7.Qe2 cxd4 8.cxd4 Nf5 9.Be3 Bb4 10.Nc3 Qa5 11.Bd2 Ncxd4 12.Bxd7 Kxd7 13.Nxd4 Nxd4 14.Qd3 Nf5 15.O-O Rac8 16.Rac1 d4 17.Ne4 Bxd2 18.Nxd2 Rxc1 19.Rxc1 Rc8 20.Rxc8 Kxc8 21.Kf1 Qxe5 22.Qc4 Qc7 23.Ke2 Qxc4 24.Nxc4 f6 25.Kd3 Kc7 26.g4 Nh6 27.h3 e5 28.Ke4 Nf7 29.Kd5 Ng5 30.h4 Nf3 31.h5 h6 32.Ke4 Nh2 33.f3 Kc6 34.Nd2 b5 35.Kf5 Kd5 36.Kg6 Nxf3 37.Nxf3 e4 38.Nd2 e3 39.Nf3 d3 40.Kxg7 d2 41.Kxh6 d1Q 42.g5 Qxf3 43.g6 Qf4 44.Kh7 Qc7 45.g7 Qxg7 46.Kxg7 e2 47.h6 e1Q 48.h7 Qe7 49.Kg6 Qf8 50.a3 a5 51.b3 b4 52.axb4 axb4 53.Kf5 Kd4 54.Ke6 Kc3 55.h8Q Qxh8 56.Kd5 Kxb3 57.Kd4 f5 58.Kd3 Qd8 59.Ke2 Kc2 60.Kf3 Qg5 61.Ke2 b3 62.Ke1 b2 63.Kf2 Qf4 64.Kg2 Qg4 65.Kh2 f4 66.Kh1 b1Q 67.Kh2 Qg3# {lamborghotti won by checkmate}

I think, like me, you need to think more about your minor pieces and imbalances.
The outcome of your 10 .d4 - you put your pawns on dark squares and trade off the bishops - doesn't seem particularly worthwhile to me. You've traded a piece, leaving yours and your opponents knights on equal footing, and left those pawns a bit too advanced for the support they can be given.
I think in that position it would be better to think of ways to make your bishop a "good bishop", and your opponent's a "bad" one. I don't think that means doing anything solid towards that goal right now, personally Re8 looks most appealing to me - supporting the central mass and developing a piece - but if a bishop trade is offered, avoiding it. But a future Rac8 followed by say Be6 and Bb8 looks like a great setup using the open file and long diagonal.
Instead you enter an equal knights position which quickly peters out. Any chances which popped up were pretty much a matter of chance by this point I think. then the knights come off, then the queens then... well maybe someone else can give you an endgame analysis, but personally I think you need to work on your middlegame. Think imbalances!

for starters to improve faster you should resign in totally lost positions
e.g. move#44
In my opinion you should not resign. Even if you play on and lose you might learn something. Plus, there is a tiny chance that you could pull of a draw. Tell me if I am wrong, but I think resigning is bad. Just my personal opinion.
I am a high C class player looking for a high level player to look at this game and tell me what my biggest flaws in this game are, and what I should do to improve going forward.
[Site "Chess.com iPhone"]
[Date "03/19/2016 11:11PM"]
[White "angelmaquea (1551)"]
[Black "mr_hellie_hansen (1565)"]
1.e4 e5 2.Bc4 Nf6 3.Nc3 Bb4 4.d3 c6 5.Nf3 d5 6.exd5 cxd5 7.Bb5 Bd7 8.Bxd7 Nbxd7 9.Bd2 O-O 10.O-O d4 11.Ne2 Bxd2 12.Nxd2 Nc5 13.Ng3 Qd7 14.Nge4 Nfxe4 15.Nxe4 Nxe4 16.dxe4 Qc6 17.Qd3 Rac8 18.Rac1 Qc4 19.b3 Qxd3 20.cxd3 Rc6 21.Rc4 Rfc8 22.Rfc1 Rxc4 23.Rxc4 Rc6 24.f3 Kf8 25.Kf2 Ke7 26.Kg3 Ke6 27.f4 g6 28.Kg4 exf4 29.Kxf4 h6 30.h4 f6 31.Kf3 f5 32.exf5 Kxf5 33.Rxd4 Rf6 34.Rf4 Ke5 35.Rxf6 Kxf6 36.g4 Ke5 37.Ke3 g5 38.h5 Kd5 39.a3 b6 40.b4 a6 41.a4 Ke5 42.d4 Kd5 43.Kd3 b5 44.a5 Ke6 45.Ke4 Kd6 46.d5 Kd7 47.Kf5 Kd6 48.Kg6 Kxd5 49.Kxh6 Ke6 50.Kxg5 Kf7 51.Kf5 Kg7 52.Ke5 Kh6 53.Kd5 Kg5 54.Kc5 Kf6 55.Kb6 Ke7 56.Kxa6 Kd7 57.g5 Ke7 58.g6 Kf8 59.h6 Kg8 60.h7 Kh8 61.Kxb5 Kg7 62.a6 Kh8 63.a7 Kg7 64.a8Q Kxg6 65.h8Q Kf5 66.Qaf8 Ke6 67.Qhf6 Kd5 68.Qc5 Ke4 69.Qfe5 Kd3 70.Qcd4 Kc2 71.Qe2 Kb3 72.Qdb2# {angelmaquea won by checkmate}