Tips for coparenting with Aries male

If u read my last post you'll have the background that I had an extremely fast/short relationship with Aries man who is now the father of my twins. Any who I was wondering if anyone could offer some helpful insight into the Aries mind so I can best know how to deal with him trying to co parent. So some issues I've been dealing with is he'll go weeks without checking on them and then when we do finally talk he always bring up "relationship problems" we had in the past. He lied about who is was and cheated while we were exclusive for only a month but he's determined somehow to put me at fault for everything when I try to change subject back to the kids. For example he'll say the girl he cheated with was just an one night stand and he didn't want anything more with her (like that matters, he still cheated) also I posted our sonogram on FB and that's when women inboxed me that he was cheating, so he blames me for finding out cuz I posted the pic. Lastly, he keeps bringing up he brought a plane ticket to see me but I told him I didn't want to see him after everything I found out. How could he expect me to?? I want to focus solely on what's going on with the kids but it's challenging when he diverts back to issues of the past. If u have any tips on why he hasn't moved on from the past to help me better address them that would help or any helpful tips🙂