Losing weight

I’ve been struggling years, to lose weight, and lately, I can’t even bare to look myself in the mirror. My boyfriends says I’m perfect, but I feel he’s just being nice. I’ve never been skinny, I’ve always been on the thick side, but now it’s not being thick, I’m just really big now. I used to weight 170, and now I weight 258. I don’t mind being slightly chubby, but I just don’t know what to do. I want to work out like crazy, but I don’t have the motivation anymore. I try, but I feel like a disappointment to myself. What should I do?😔