1. Yes, your mother is entitled for maintenance from you if she does not have any male child living.
2. In any event whether you have legal liability or not you being her daughter can not leave your own mother to lurch alone .
3. So shun these ideas She has no one else except you and she being your own mother must not be ignored at he cost of your child. Do not forget she gave broth to you and reared you up as well. now at the time of her need you must not be selfish and fulfill the duty of a child which he woes to his parent.
Good luck.