Guys and their porn...

Megan • 23; pregnant with my second boy! And engaged to my best friend.
Ok, might be long. Beware. lol. Just need to vent to some ladies. 
I'm not all into my fiancé watching porn. I know it'll happen, because I'm 6 months pregnant and my sex drive has gone waaaaay down. Lol I get that. But I've told him it really upsets me, mostly now because I'm very insecure now that I'm pregnant. Don't feel cute or sexy at all. Normally I'm 110lbs and now I have this big basketball under my shirt. A few months ago, I went off on him for watching it because I thought I was giving him enough of what he wanted before my sex drive went down. But apperantly not. Just makes me feel like shit about myself. Honestly. And when I "caught" him then he tried to lie when I legit WALKED IN on him watching it. I think that's what made it 100% more worse, that I seen with my own two eyes. Him gettin off on some other bitch. Lol anyway, watching porn is obviously NOT a deal breaker for me.. I love him with my whole heart. And he's an amazing step dad to my son and soon to be daddy to our second son. He's honestly the BEST fiancé to me!  but man. I'm not sure how else to explain this to him. Or at least just get over the fact that he's gonna do it. He doesn't do it like every damn day. Idk when he does. And honestly I don't care. It's just the face that he does. Just hurts me and makes me feel im doing such a shitty job at pleasing him. Any advice would be nice. No rude comments.