How can I cope with these problems?

I am 19 years old and am at university in London. I have been told by a counsellor when I was 18 years old that my mum has emotionally and mentally abused me as she would control what I wore and how I spent my money. She had a really bad temper and if she was in a bad mood she would take it out on me rather than my brother who is 20 years old. My parents are divorced and my dad pleaded with me to take my offer of university as he thought it would be an escape from her being nasty to me and dominating my life. But while I have been here I have given her �400 and I have never seen any of it again, she has run up debts on her credit card and took out a loan of �14000 when I was 8 years old and I was not aware of this until I was 16. She manages to twist her money problems around on me and makes me feel like I am responsible for it. I gave her the �400 to help her with her debts but she has done nothing with it. When i speak to her on the phone she never asks how university is going because she resents me for coming to london because she is no longer able to control me. She piles her problems onto me about money, asking me for more and saying she has nothing in her life. She recently said in a spiteful way that I have everything to look forward to and she has nothing, as if she is jealous that I am 19 and have my whole life ahead of me. She continuously moans about my brother and his girlfriend to me and they havent done anything wrong, she will moan about small things like petrol and work and she has been to see a debt counsellor after I begged her to try and sort out her money problems. She has told me all about her problems but she never speaks to my brother even though he lives in the same house as her! He knows nothing about any of it and she keeps piling her problems onto me, making me feel guilty for being at university. She takes no interest whatsoever in my life here and when I go home she turns back into the dominating mother she has been for so long. She told me at Xmas that she wanted this particular present and I bought it for her and something else as a surprise, a chocolate plaque with a xmas message on it and she looked at it all and said she always gets rubbish presents and she ruined the day as she does every year by moaning about how she never has any money. I literally cannot cope with her pressurising me for money and I feel bad if i say that I cant give her anymore money because I need it to live on. I have got myself into debt by giving her money because she is demanding some every few weeks. My brother and her argue everyday and she says to me that she worries about him and she never mentions that she worries about me as well. I literally cannot cope with it all, its too much pressure and I dont want to go home for summer, I would rather stay down here away from it all. University was supposed to be my escape from her and her dominating ways but it seems to have got worse especially where money is concerned. Can anyone please advise me? I am literally depressed by it all and keep crying about it and my friends are worried that I am going to have a breakdown eventually. Please help!