I am no 1900, but I don't like your strategy from move 36.
You have much more pawns on the king side to sort out to create a passer, so you have to be much more active and forcing, otherwise he will start pushing his passers on the queenside.
36. should have been Be2 e5
The more moves he has to make on the right, the closer you are to the victory.
You delayed e5 until the move 41! By that time the opponent managed to get all his pawns rolling plus put his king to support them.
I'm on a roll recently. Lets put aside my failure to take advantage of a fairly nice middle game position. Its my poor play in the endgame that I would enjoy comments/analysis on. By move 40 or so, I think in hindsight I have an advantage. I've got a huge kingside majority with my Knight positioned to help push my pawns. Instead of staying aggressive, I retreated my Knight due to concerns about my opponents counterplay on the queenside. I read in Silman (Amateur's Mind) that this mental mistake is common by amateurs like me. But it was hard to calculate so many moves ahead, even with the help of the analysis board, let alone had this been OTB. Was my judgement a mistake? I think so. What kind of lesson should I draw from this game, other than to try to improve my endgame calculation skills?
By around move 50, I was thinking the game would end with a draw. Then I made a one-move slip and the game was over.
Awesome!