Is there anyone that can go check on her that lives closer? Neighbor, coworker..?? And...if it were my mom and I had exhausted all possible avenues...I'd go. Depression isn't something to play around with. Good luck....
I'm sure she'll appreciate your company and concern for her well-being.
Have you tried calling on the phone?
If you can't call her or call a neighbor, then I guess that train ride is in order.
is there anyone else closer by and ontop of that she could just b sleeping some antidepressenets make you tired and you wont wake up for the phone