I'm probably a lot older and I lost my mum a month ago, but I had the opportunity to pick up my life and retrain at 49 - within walking distance of home, as it happened. My family were all for it, but my mother needed an operation (which was the start of the dementia but we didn't know it then)and another student on the course (we were all older) said it is not the job of the young to look after the old. I was so angry and thought her quite heartless. It was five years before I did the second year of my course, missing all sorts of opportnities, and even that course wass difficult - it wasn't the content, it was trying to do the paperwork at home. Another five years later and mum moved in here permanently. I had two hours work a day if I was lucky and that was my only escape. I felt like a prisoner in my own home. I'm 59 now and I wish that I'd done things differently - if I could have.
I wish that I'd known what was coming - no-one mentioned dementia until I worked it out last summer and asked for a diagnosis.
I wish that I had refused to take mum in and looked for residential accommodation instead. Wishful thinking, I wouldn't have done it, but I should have done it. Mum would have had company and I could have spent quality time with her. If I was a man (with apologies to men everywhere) I would have done it because I would have given the need to earn a living and support my family a higher priority, but knew that we could just about manage on my husband's income and some part time income of my own.
All I can say is, it is probably better to start your studies and then have to take a year out than not to start them at all. And if my mother had realised, outside of her dementia, as a normal person, how much her illness affected me, she would have been so unhappy. GPs and Social Services can do a lot, but only - in my experience - when the need is perceived as critical. Whilst I was living in my own home and mum was living with me the social services said that it would never be critical until I reached the stage where I could no longer have her living with me.As your mum would need more help if you are away, it is possible (I hope) that she would get the help that she needs.
I know you miss her so much. In the end I hated my demented mother but I still loved my mother, if that makes sense, but you can't always put your own life on hold, either. Not always.