You need to look at the game as a painting of pieces on squares and empty squares. Singling out one piece on the board is what is making you make the mistakes. It's like getting into a car accident because you only look at the car in front of you and not the cars on the sides and further up.
Whenever I am a queen up, I like to message my opponent and say, "Me winner, you loser." That helps too.
I never trash talk or make arrogant comments to my opponent, that seems like it would just make them drag it out even more instead of resigning. I know whenever someone types "gg" or something before the game is actually over, then I'll drag it out to checkmate when I ordinarily would just resign.
Clearly I need anger management... but does anyone else get really, really mad when they either
1. Lose a game they clearly had won/drawn
2. Have a completely winning position (i.e. up a queen or something similar) and the opponent doesn't resign.
#2 gets me so angry that I often end up blowing the position because my concentration is shot and my emotions take over. I find #1 happens way too often as well. I got so mad today, this happened.
How can I stop blowing clearly won positions? I hate this so much.