Hi there,
I can see why you are so angry. I would be too, put in your position.
I think your mum has been putting you in a difficult position. I agree with you, she should be able to look after herself. She is playing the "helpless me" part. She sounds a bit manipulative to me. The difficult thing is that she is still your mum. They have a way of making you feel guilty no matter what you do. I can see that you really do care for her, even though she has been making things hard for you. Your uncles etc don't seem to be very helpful either. Relatives - you cant choose them....
I would be careful to take her back with you. Is this really what you want? You have a life too. I don't want to sound cold, but you should think about yourself sometimes too. What was your mum doing at your age? Was she looking after her mum, or living her life?

Lisa