Finding my compelling reason to lose weight

I am really struggling to find my compelling reason to lose weight. Last year I lost 40 lb and then gained it back. Even though I felt better when I was thinner I didn’t feel that much better. Now when I think about the work and sacrifice it takes to lose all that weight again I don’t think it’s worth it. Of course deep down I really really do want to lose it. I’ve wanted to lose it for the past 25 years. Maybe it has to do with my wanting to feel that I am lovable and worthy whether i am fat or thin. I think I have some resentment from when I was younger about my weight. I feel like the message I got from my parents (but mostly my mom) was that I would be more lovable and acceptable if I was thinner. My outside was that important. I may have reacted against that by saying “go to hell, I can be who I want to be and look however I look and I still have value.” I have never been one to dress really nicely, do my makeup and hair and all of that. Don’t get me wrong, I am clean and all but just don’t go all out on all of those things. I do on occasion but not on an everyday basis. I have always felt like it’s a waste of time. Now, I am 53 and want to feel good about myself. I want to wear cute clothes but I don’t fit in the cute ones. I wear plain, practical clothes that are often baggy. I value being “comfortable” but maybe I’m just hiding behind that. If I were to do a model it would look like this:
C: I am fat and don’t feel good about myself
T: Being thin means I have sold out to social norms and I waste my time doing stupid things
F: feel good (eat anything, anytime) feel bad (am fat and don’t feel attractive or good about myself
A: eat what I want, exercise when I feel like it
R: I stay stuck in a cycle of losing weight temporarily if I diet but ultimately staying fat and not feeling good about myself

Help!! (Please??)