having a hard time losing weight need help

hello everyone one, im 5'3 and I been having a hard time losing weight the big cause of me to gain weight is nexplanon birth control before I had it I weighed at 120lbs it been about 4 years I haven't had it and I now weight 231 lbs I tried to be motivated but it's very hard when I was Skinner I was self conscious about everything about me and now that I I'm fat I beat myself up with words I had family members saying how I don't look good in certain clothes I have them bragging bout someone else that's way Skinner then me I have them offer me food knowing I can't say no especially if it's something I love... I have stretch marks like I had a baby I want to get fit I want to be those people to wear what they. want n not get judge about it I have back pain every single day standing too long hurts me even if I was doing the dishes. please give me.advice im tired of living like this I never really had supportive people.