You are neither a sucker or a fool. I can't believe that she's a quilter herself and she only gave you $20! That is outrageous! To get out of the other 2 quilts she asked you to do, I would just tell her that you are so sorry but you had a couple of other projects that you had already agreed to do and you don't feel right not being able to put your time and attention in to those projects. You wouldn't be telling a fib because every quilter has at least 5 or 50 other projects they have promised themselves to do when the have the time.
So sorry this happened to you.