Is there anyone else you know who can give you a lift?
And about your xp not doing anything - can you pin him down as to whether he is prepared to pay for the repairs or not? And if not, will he sign the car over to your name so that you can pay for them (I know you haven't got the money atm but cross that bridge when you come to it).
If you have to do the bus thing, explain to him how very difficult this makes the lives of his children. If you say it will make your life difficult, he'll be pleased, but if you put it in terms of how it makes the children's lives difficult, he might feel obliged to pretend he gives a shit.
What a w**r he is. Sorry Rickman.