One of the things I have finally learned is that it is okay to put myself first sometimes. Many of us were raised to think that we had to be 'noble' and submit to the wishes of someone else, no matter what we wanted. If we didn't, the guilt would set in.
Well, maybe one of the lessons we are supposed to learn while in this lifetime is to honor ourselves. If you don't want this person sponging off you and your husband, it is OK to say that and to not let anyone make you feel guilty about it. Just my humble opinion.