Hi there,
I take it you are no longer together, so you don't have to pay for any gift that he has decided to get for her. It's on him to pay for her gift from him, as you have for her, yourself paid. I can understand splitting the cost of a party, but she doesn't want that. You are not obligated to pay for the gift just because the party isn't taking place.
Don't worry about it, if he wants to spend alot of money on her gift, that is his decision. If he is that upset, he will reconsider his gift, and cost. Besides, you got her a great thing....clothes!
Good luck! :-)