i resign if my opponent has a rating 150 more than me and he is 5 ahead.
Resign after blunder?

"It's never too late to resign" Here is a good article about this theme. Read it https://chessmood.com/blog/it-is-never-too-late-to-resign-in-chess

At least at the intermediate level don't resign as you may discover a fork or pin that will even out the game. And there are players out there, even at 1000, that will carelessly attack and generate a stalemate. I had some crazy wanting to get 3 more queens. He could have played smart chess and had me in 4 moves. Instead the generation of his fourth queen resulted in no legal moves for me and a stalemate. Do I feel good? No, I messed up the mid game BUT I bet he learns how to checkmate without an army of queens. So I looked at it as a teaching moment :-)

Chess.com should be setting you up with people at your level. If you are only a 500 you are not going to be playing an 850.

I've been down several pieces and end up with a win or a draw. Blunder is part of the game. I hate people that resign too early, even if they help my rating

I've been down several pieces and end up with a win or a draw. Blunder is part of the game. I hate people that resign too early, even if they help my rating
why...
its their right..

at the first place its not your business at all, if somebody resigns or not.. its their time and they should do with it whatever they want...
and secondly there are positions what are just hopeless.. i not gonna desperately try if my opponent will do a misclick accidentally or lose due a bad internet connection... thats not type of win what would make me happy
Do you resign after a blunder?
I consider it bad form to continue to drag out a game when down a piece. The flip side is that my opponent may also blunder if I continue, but what is the point? Then I develop the Habit of the Sloppy Game.
Depends which piece I blunder and how high my opponent is rated. Usually for high rated players, a blunder would mean a lost.