Warning: long post

I feel like my world is falling apart. There’s a girl we’ve had disagreements over for probably the past year. He would hide their conversations, look up her instagram often, and saved pictures of her in the chat. I obviously get upset, and he knows how I feel and jokes about it but sometimes reassures me. Two days ago, he brought her up randomly. Later on, I asked if they were talking again, he said yes, and I asked him not to follow her. He said okay and unfollowed her. Later on, I happened to see he was following her again. I obviously felt hurt and lied to, so I brought it up. He denied following her again, and I assume quickly unfollowed her before showing me. I wanted to see what they were talking about that made him so adamant in following her because I felt he wouldn’t be honest with me if I asked. I logged into his Snapchat, and he saw yesterday. For a while after, he acted fine, fairly normal. I chose to be honest and apologized, and he said “honestly, I don’t give a f*ck.” And now he’s been between acting fine and then being cold and distant. I texted him today asking what steps I should take to help us get back to normal because I do understand why he’s upset, and he told me he couldn’t tell me. I told him I texted because I knew I’d cry if I said it all out loud, and he said he texted because he “didn’t want to” say it out loud. We moved to a new state and I don’t really have friends or anything yet, so I’m feeling super alone. For background context: he used to frequently use pornography in literally any way possible (other girls he knows, tinder, onlyfans, sites, saved snippets of movies, etc.) He also has PTSD. There’s been multiple times I’ve called him out on his behavior in the past and he’s asked for a divorce and then taken it back or given me the silent treatment. I don’t know what to do to make things okay again. I just want to go back to how we were two days ago.