Yes, Elias should have used contraception himself ESPECIALLY after the first unwanted child.
BUT as far as I can see he's just feeling bad about being a father who doesn't really want to BE a father. He loves his kids, but doesn't want to be a hands on dad.
In most situations like that, Mom gets to be main caregiver, and Dad gets to see his kids on occasion... and everyone is happy! (Well maybe kids would like to see dad more... but most kids I think don't like swapping houses week in and week out...)
It seems to me that Elias is just acknowledging his feelings in an honest manner?? Yes, he's a dad now and he has responsibilities...he's not trying to palm them off I don't think... but he's at least being HONEST about the way he feels.
Lots of people get pregnant and have kids despite using contraception... some of them make lousy parents and don't give two hoots about it!