NEED Relationship Advice

I normally wouldn’t be posting anything about my relationship but i have nobody to talk to.. any advice will be much appreciated! okay where do i start... (this may be a little long so bear with me) i’ve been with my babby daddy 2yrs & 8mons now. we have a 5 month old baby boy. My baby daddy & I have gotten to multiple arguments because i find on his fb that he’s liking pages that have naked females all through the page. Idk why it bothers me to see that. I get so hot inside like i just want to go off on him because i’ve told him many times before that i don’t want him liking nor following pages of girls like that & he would promise to stop doing that & he would unfollow all the pages. I try to not go through his phone because i want to trust him. I found out because he asked me to turn his alarms on & that’s when i saw a notification staying “he had been approved to fallow “ “ page”. I want to go off on him so bad but idk if i’m over reacting? what should i do? im so mad because we have been through this to before & he don’t seem to get it through his head that it bothers me seeing that he’s liking and following groups on facebook of females posting nudes of themselves or pages of half naked females. I wouldn’t even have the heart to be looking at other men & following pages with naked guys because that’s just out of respect you know?, but i would like to hear some options & advice im really stuck here & im trying to maintain strong in the mean time.