I want to lose weight…but it seems hopeless

Ok so I have started going to the gym… it makes me really insecure. I weigh 217 pounds while being 5'1. I used to be curvy and but I have also always struggled With eating  disorders. My weight constantly varries. 6 months ago I weighed 170… 4 months ago I weighed 180, now I'm extremely obese. I miss having a big butt and boobs. Now I'm just curveless and I only have a belly. I feel so worthless because I get made fun of a lot and I don't know what to do. I just want to look how I used to. I want to be beautiful… Idk how I let things get so bad. I need tips on how to cope and how to lose weight. Pretty please