(21M) I have no self confidence after my ex cheated

Hey all,I has been almost 8 months since I caught my ex boyfriend of one year cheating on me. I haven’t been with him since. I got into another relationship and the guy broke up with me two months in, with no explanation.I just have no self esteem. I wear coverup, I can’t leave the house without looking at the mirror 10 times, and when I’m in public — I avoid the mirror and pictures.I have made tremendous strides in the past couple of months. I have been going to the gym almost everyday, dropping weight and putting on muscle, but I still feel horrible emotionally.I feel kind of inferior to my ex boyfriends because they where very attractive.Anyone have a problem like this? If so, how did they deal with it? I’m deathly afraid of being alone forever.Thank you!