Unless you really screwed over your ex don't give them anything. Give your money to a local homeless charity, if you don't trust them then volunteer at the charity, It's pretty hard to embezzle your time. Find people in need in your community and help them if you really want to build up karma, trying to help out your ex is just going to be a form of self serving conscious cleaning.
The coof has caused a lot of people to be in need, use the internet to find them and help them out.
All that being said if you really got to help her out, just send her pizzas everyday.