I think that you should stay at your current school. Don’t transfer back home. Like you mentioned, your mom could live for years. If this was something that was imminent…like in the next month…I might be giving you a different answer.
I don’t know your mom, but I am a mom and I know that if I were in your mom’s shoes, I would want what was best for my kids…and that would be for them to stay in school and to not transfer just because of me.
I’ve also had to deal with the oncoming death of my terminally ill mom. She had pancreatic cancer and lasted 18 months from diagnosis to her passing away. In those 18 months, I was only able to see her 3 times in person. The last time I saw her, it was about a month before she died. But I have no regrets. We lived practically on opposite ends of the country from each other and at the time, my kids were really young. Plus, I was working full time in a contract position (i.e., not a regular full time employee with benefits) so when I didn’t work, I didn’t get paid. And we couldn’t afford for me to not be working. Nor could I afford to pick up me and my kids to the other side of the country and just wait. I talked to my mom on the phone every day. Often just to tell her that I loved her. When the end was getting near and she was sleeping a lot, I’d still call but my dad or my sister (who took time off of work to help my dad care for her) would put the phone on speaker or hold the phone up to her ear so she could hear me talk. When she went into a hospice facility, I did the same thing. Even when your mom reaches a point where she can’t speak and she seems incoherent or totally out of it or she sleeps all the time or is unconscious, she will know that it’s you. She knows your voice and it’s ok if you can’t be there every single day. She will know that you love her with all your heart.
Your mom would probably not want you to put your life on hold. Seeing your child live his/her life to the fullest is what makes a parent’s heart soar.
There is no right or wrong answer to your question. It’s a very personal decision and you should do whatever you feel is best for your unique situation.