Why don't you charge him for the vet expenses involved with your bitch and maybe something for harming her through birth? And maybe you can get a new family, toss out all the chaos which may involve your BF. ... So anyway, I'd say to the major nut case "You are nuts. If any one owes anyone anything, you owe me. I am not hearing any more of this." and repeat the same thing to any one else that's on his page. Say it once, maybe twice than just "I will not talk about this." Beyond that, no more watching their dog(s), their child(ren).
It doesn't sound to me like you need the chaos these folks add.