I need some advice.. Hopefully nothing negative please

Well I am almost 18, and I'm dating a 21 year old guy.. Which I live with him. And I look at his phone every once in awhile which he doesn't care we both are open to each other. I have been looking, and I seen he watches porn.. which inside I just feel hurt, and disgusted because I feel as if it's creating a fantasy of what he wants during sex, and I'm not the prettiest girl so I'm super insecure.. To be honest I get sick when I find it.. Cause I figured he would come to me if he wanted sex cause I give it to him whenever he wants it. But I need some advice i don't know if I should say something or just ignore it because it's ok? We fight sometimes, and I don't know if I should say something cause he might get upset. Some one just please help cause idk what to do or how to get over it..