You know, you don't even have to state why you want your money. It is so obvious that your money should stay in your hands.
It is hard to stand up for yourself because you don't have the habit to do so. But it is important that you learn, so that you can teach your daughter how to protect herself.
The confrontation feels so hard because it is your Mom but many times in life we have to stand up for ourselves.
Give yourself a big hug, tell yourself how much you appreciate your own courage and efforts. And then do it!!
I send you a big hug