Self esteems and sex

I have to get this off my chest.

I feel bad and like I’m selfish, but this issue has cropped up a couple times but now I feel like its an all time worse for me. My bf and I have sex maybe once every two weeks if I’m lucky and I told him I understand because he said he’s never had much of a sex drive. And I’m the opposite but understanding. Lately though, or maybe I’m just noticing it, he has preferred masturbating instead of having sex with me, I’ll see his set up of pillows and his fleshlight toy out so it’s quite obvious he has done his deed... this doesn’t upset me so much but its his reactions when I try to get a little more sex out of him. He’s physically pushed me away and moved my hands. Pretty much flat out rejects my attempts to have sex. I just feel unwanted by the situation. I feel ugly and fat and has really been taken its toll lately. He has the sexual energy to jerk it 2-3 times a week but not have sex with me.... i feel im overacting because he still gives me compliments but to me they feel forced because of his lack of interest in me. Its gotten to the point i hate myself again because i dont look like the girls pictures he likes on tumblr or like the girls in porn. I’ve broken down and cried so many times. We’ve been dating maybe 3 years almost and i love him but i just feel so.... undesirable