Wow, that's not cool. You can score better than cheats OP.

yeah op could probably find someone way more respectful

Unclear relationship boundaries suck. Unless both sides know about them. In which case they aren't unclear anymore. Case closed.

time to fire up that tinder...

Go out in a blaze of glory.

I would run from that relationship faster than bank account drops after payday.

Is he really your boyfriend?

Bare minimum you shouldn't have him in your bed again after that.

You don't need a man who is comfortable enough to share his cheating on social media

Or comfortable with cheating at all really.

I don't want to be 'that' guy, but if this isn't agreed on by the both of you, you need to break it off with him.

I don't think you're being "that" guy. I think that's what everyone else was thinking and it's pretty apparent that this wasn't agreed upon.

I'm pretty sure he posted those pictures because it was his horrible way of breaking up with her. Either he didn't want to be the one to do it, so he slept with his ex to force her to, or more likely, he wanted to break up with her and hurt her so he slept with his ex and posted pics that he knew she (and everyone else) would see. He obviously knew his relationship was over the moment he posted those pics, and it sounds like that was his intention all along.

I just figured it's better not to say "You mean ex, right?"

Sorry op you can do better

and thus the moment he became single and you to look for a better man that deserves you. :)