This may sound nasty. Pay the woman. You really didn't think that you could receive professional services at no cost indefinitely did you? If you have the money to help your mother, then you have the money to pay your Pdoc. I am certain that she feels disrespected by your lack of payment when you are financially supporting someone else. I would be livid if someone told me that they were giving money to someone else while I was providing a service at no cost that I could charge $200 an hour for.