I think my mouse is going to be alone

So, I had 3 mice. 1 mouse died 2 weeks ago of old age leaving only 2, one is looking really old and showing signs of passing and one is starting to look older but I’m afraid the one is going to be left alone. I can’t get any more mice because I leave for college soon. I don’t know what to do when she is alone. It’s impossible to play and be with her all hours of the day, I mean I have school and work. What do I do? All advice welcome