Is this a good reason to breaking up?

I've been dating my boyfriend for a year and half now. To be honest, I've never felt really good enough for him. I will eternity believe that he's cheating on me because he is the type of boy who adds 100 pretty girls on Facebook and likes 300 on IG every week. I've seen those girls and they don't look nothing like me. I have no boobs, I don't consider myself pretty, I'm shy (which he is not, he's extrovert) and our body's sizes are not normal (sometimes, I look bigger than he). Even, when he tries to cheer me up, I can't convince myself that he likes me and that he's not cheating, maybe due to the fact that we barely have sex. Lately, I can't get rid of the idea of breaking up for good. I mean, I don't deserve him... I know his family or friends don't like me at all. And off course, I'm getting so tired of this feeling of angry on my chest. The fact that I feel totally bad about myself makes my confidence go ⬇ and ⬇ everytime that I'm with him. Actually, it feels like I'm feeling envy for not being as charming as he is and it makes me MAD! I'm the typically ugly girl that God knows how got the man. I m still crazy in love with him but I don't think we belong together.