I'm giving up on sex

Rant time! Sex just doesn't feel good like I had hoped. I think it's something wrong with me, my boyfriend thinks it's his 4 inch dick. I don't know which of us is right, but I'm just sick of not being able to cum. I used to just have sex for the intimacy but I just started getting really frustrated because it's not fair that he gets to cum every time and I don't. I could never have an internal orgasm, the only way I can is if I ask him to stimulate my clit afterwards, but even then we both agree that it's awkward and not as intimate and enjoyable experience.. So I'm just done. It really just pisses me off it never lived up to my expectations and I wish I could make it better.