I really need to ask, and I don't intend to sound as dickish as this may sound, but while I understand that the folks here are your friends, and you respect their opinions, but seeking advise on what I would consider truly life altering choices that quite frankly will only have a positive or negative impact on you, not the people responding to your tale of woe, just seems a little crazy and perhaps, as James hinted at, a little bit of your need to have others involved in your drama.
Perhaps it's the parent in me (I'm the stepfather of a mid 20 year old son that I've been "Dad" to for over 17 years), but you really need to take charge of your life and make the hard choices that only you can make. I'm not going to tell you what to do because I have "no dog in the fight" as they say - anything I would tell you would have no impact on how the choice you make will affect your life. To be honest, it sounds like your "mum" needs to do the same - speaking from experience, it's never too late to make life altering changes in ones life. Ultimately the only person your are responsible to and for is you.
I'm going to share a few quotes with you that have had a profound impact on my life and recommend you read about the man they come from.
"... everything can be taken from a man but one thing: the last of the human freedoms—to choose one's attitude in any given set of circumstances, to choose one's own way."
"Each man is questioned by life; and he can only answer to life by answering for his own life; to life he can only respond by being responsible. "
"Live as if you were living a second time, and as though you had acted wrongly the first time."
I know they sound very new age-ish, but they are from Austrian neurologist and psychiatrist Dr. Viktor Frankl (1905 - 1997). He was a Holocaust survivor that wrote about his experiences in Theresienstadt concentration camp during WWII. He wrote extensively about these experiences in his book "Man's Search for Meaning" published in 1959. He was the creator of a form of existential analysis called logotherapy which is focused around the tenet that the "striving to find a meaning in one's life that is the primary, most powerful motivating and driving force in humans." In this book he talks about many things, but key to understanding his theories is that we ultimately can only control our response to the situations around us and not the conditions that lead to them. At the heart of mankind is the freedom to choose ones own reaction to what may be horrible situations we find ourselves in. We can give into these situations and give up, or we can "choose" to respond differently and to find meaning in our lives.
Another quote that explains this thought process is this:
"We can discover this meaning in life in three different ways: (1) by creating a work or doing a deed; (2) by experiencing something or encountering someone; and (3) by the attitude we take toward unavoidable suffering."
With this quote he tells this story to explain these principles:
"Once, an elderly general practitioner consulted me because of his severe depression. He could not overcome the loss of his wife who had died two years before and whom he had loved above all else. Now how could I help him? What should I tell him? I refrained from telling him anything, but instead confronted him with a question, "What would have happened, Doctor, if you had died first, and your wife would have had to survive you?:" "Oh," he said, "for her this would have been terrible; how she would have suffered!" Whereupon I replied, "You see, Doctor, such a suffering has been spared her, and it is you who have spared her this suffering; but now, you have to pay for it by surviving and mourning her." He said no word but shook my hand and calmly left the office."
So - after all this typing I guess I'm also refraining from giving you an answer other than to tell you the choice is yours to make, yours to come to grips with, yours to find meaning in.
I hope you take this with the intent that it was meant - I think you are a skilled musician and it would be nice for you to make a living from it, but you also need to start taking charge of your life and taking responsibility for your choices and your situation.
As the anonymous friend I am, that's all I can tell you.