My abusive ex was nicer after we split up! Yes my normally verbally abusive and often physically abusive spouse was quite friendly after I told him it was over. We had an amicable relationship before my daughter told me he'd abused her, and even then when I had to deal with him following my son's head injury we were still able to set aside our feelings and be far more civil to each other than this guy is being.
I realize his (divorcing guy's) parents spent years being nasty to (and about) each other after their divorce but you'd think he'd learn from that rather than emulate it. He ought to think about how it made him and his siblings feel to always hear them talk shit about each other. Even now his daughter can pick up on his tone of voice and things like slamming a car door in her face. He keeps talking about how this divorce is affecting her--but he's making it worse.
Working out custody and visitation isn't pleasant but it doesn't have to get so nasty.