Okay, this is about business then. No please, please, please e-mails EVER again. This is business and not personal.
Tell him that his amount for the vet bills is X and let him know you need it by X date. Or if he prefers to go the the vet clinic himself and pay it, that is okay too. this way you take yourself out of harms way, in case he wants to spew on you. You take that away, see?
If he doesn't pay in the time that he agrees to, tell them that you will have the vet clinic contact HIM regarding payment due.
No more begging with this guy. He feeds on it and he likes it right now. He likes that he has control over some aspects of your life. Don't let him do that.
You need to maintain control for YOUR self-esteem. Forget about him in this instance. Don't feed his monster.
Aug '06: H moved out July '08: H had a kid with the OW May 12 '09: emancipation day
"Life moves pretty fast. You don't stop and look around once in a while, you could miss it." -Ferris Bueller