How to feel confident with small boobs

I know all the “pros” that people usually tell me. I can wear bralettes or cute things. I can sleep on my stomach. I don’t have to worry about back pain or under boob sweat or Whatever. But I don’t care about all that stuff.

I fee disgusting, ugly, and like I’ll never be as attractive as someone with boobs. I have a decent size A cup. But I’m still that. An a cup. I hate my body, I hate looking at myself in the mirror. I am filled with so much resentment towards myself for the way I look. I hate going out in public because my boyfriend will look at other girls and claim he doesn’t. I’m so nervous to bring him around my brothers new girlfriend because I know he’ll lust after her and he doesn’t do that with me. He doesn’t lust after me, he doesn’t touch my boobs, play with them. But when I say I want a boob job he says he is against me getting one. I just feel so broken. I want to build my confidence, I don’t want to think about that or deal with it anymore, I don’t want to be jealous or negative. I just want to be happy with my body but I can’t. My boyfriend never asks me for nudes or pictures but when he watched porn or looked up girls they would be full busts, curvy, the exact opposite of me. And its not like he looked that stuff up and then asked me for stuff to. He just ignored me for that. (He did have a porn addiction he is working through which definitely didn’t help because he would ignore me for weeks, Watch porn everyday almost every hour when he was talking about it. He wouldn’t be able to have sex with me because he would go soft because I wasn’t porn and he would only be able to get off to that) so like maybe if I looked different he wouldn’t have needed that so much or he would be satisfied with me and want that stuff from me too? I just feel broken. I never wanted to be the girl that didn’t feel comfortable around someone who looks different then me because that’s so shallow but I am not. I hate it.