AIBU about co parents lack of interest

[Justone62]

Been co parenting for 2 years, DS is 4.
He has DS EOW Saturday morning to Sunday afternoon.
He never contacts him during the 2 weeks he doesn't see him, even after asking multiple times for him to facetime at least once a week, and he only does if I continue to ask him to.
Vaccines - twice now he knew he was having vaccines and just doesn't message to see how it went or how DS is feeling!
Should I just give up trying to get him involved more, it's so frustrating

Yes, give up.

He isn't going to be the involved partner that you would like him to be and you are clearly not together. Let him crack on doing whatever he does on the time he sees your child and don't bother contacting him in between.

If he's interested or bothered he can contact you. He won't.

You are wasting your own time and energy. Just expect nothing.

You give his contributions too much status. He's barely a parent never mind a co parent.
Just as well he'll have minimum influence on the man your dc will become.

He sounds shit. Which is likely why you divorced him !
ime of divorced friends it doesn’t improve.