Quick background:
Undergrad: High distinction in history, graduated top of class from a mid-tier UK university
Master's:
Tuition fee funded master's at a top UK university. My course was completely not what I expected (the papers I wanted to sit were discontinued the year I joined), I had a very difficult time, developed depression and had other symptoms. I couldn't sit my final exams, left for two terms and now I am back for my exams. In the period I was away was diagnosed with MS and I have depression on and off, which has worsened since I have come back because I need to deal with everything alone and I am so exhausted. And my GP isn't helpful. I want to go home because I am finding it very hard to deal with things on my own.
I don't see the value in this degree because I want to work in a completely different sector when I am done (I have a year-long research internship ahead of me that I can do from home) and I just want to get home, meet my specialist and learn to deal with my condition better. I live in another country and have access to private healthcare and can go back to my specialist. Also, I wish to apply to the US for further studies in a different subject (related to my research internship).
Should I leave? I am massively underprepared, feel ill all the time and fatigued, and my depression and MS symptoms keep getting worse.