hi, OP,
I have a mom who does similar things and it is very frustrating. She is not in debt but I've watched her spend away a lot of money.
I think there are two things going on:
1) what can you *do* about your mom's behavior, and
2) how can you feel better in dealing with your mom?
No. 2 is much easier to control. I find I'm much happier now that I've just decided that not only does all this crap she gives us goes into the trash or donate pile, as you did, but also I've stopped telling her this, stopped fighting when I get three bags of crap to put in my car after seeing her, or boxes arriving in the mail. I just say, Thanks, Mom! and be done with it.
No 1; that is tougher and I'm going to look at the other replies with you and maybe get an idea!