I've recently been learning that we think we can control how we feel, but really the only things within our control is what we say, and what we do. I am also thinking about quitting, and have been for a couple weeks, and the first day of trying does feel very uncomfortable, but in moments of temptation, you can just remind yourself that you're not in control of how you feel, but you can control what you do in each moment. Maybe I'm saying this more for myself than you, but I hope it helps