Dealing with depression & jealousy of bf ex

I just always been down on my self being the ugly sister even being voted the ugliest girl in middle school. I've always been jealous of the girls who got all the attention from guys even if they weren't as smart or as cool as me. Every time I went out or hung around my sisters & their friends I was always ignored like guys would offer them drinks & I would just stand there looking dumb. I've always been jealous & I'm not ashamed to admit I have a problem I've even been jealous of my little cousins because they got the same attention when they grew up & I just never did. So I got myself in the gym started working on myself taught myself & other young boys at my park how to play ball allot of those kids was gang banging early & I helped turned them around to get back in school. That was the best time of my life I never felt so good about myself. Then I ran into my ex who is my now bf & at first it was all good until he started bringing up his ex & I started to suspect he still had feelings for her. We split last year around this time because she came back into the picture but he swears me up & down he didn't go back to her. So I was the idiot & took him back I've loved this man since I was 19 I'm 26 now but we keep fighting about this girl. He just recently showed me her because he says he wanted me to see how ratchet & ghetto looking she was & she's not his type but it just made me extremely jealous. She's a popular attractive girl with a curvy body who can have any guy any time she wanted even mines. & I just been really down on myself & I know I need to dump him I am going to sit down & do it tomorrow when he's off & he can go & have his trophy GF who cheats & belittles him as if he's her pet. But I went for a run & hit the gym today & I must say it made me feel a little better it was still on my mind but not as bad. Yes I'm jealous yes I'm depressed but I refuse to let this stop me from being a great citizen to society I have so much to offer the world then a cute face & a fat ass even though I'm not bad talking women who's blessed in that area your great too!!! But so am I even though I don't fit societies ideal of beauty I'm still beautiful in my own way. I just want to know if there's any other suggestions to help with depression & jealousy I know getting out this relationship is number 1 but when it's over I'm going to feel so much worst & I don't know if I can handle that right now. I'm ok today though I didn't cry I held my head high I'm proud of myself but I know it's allot of work. Anybody ever been jealous & insecure & depressed from being traumatized when they were younger? How did u get over it how do you cope?