Help!

I have a 3 and a half month old with my ex N. How do those of you with children with them do it? How do you maintain NC? Mine lives 4 hours away and doesn't see her much. Has only been to see her 3 times. Likes to look like a good dad on paper but doesn't care about anything besides that. Just looking for pointers and maybe some experience from those of you who have been through this.