Saramae, your mother has a very serious form of depression, in my view, and needs psychiatric help. Is there someone in your family whom you might speak to and ask for help in getting your mother in for counseling and medication?
There is much that can be done for major depressive disorder, but your mother needs to have someone help her take action to correct the chemical imbalance. It is not healthy for her to spend her time as she is doing, and it isn't good for the members of the family who must endure it until she gets relief.
Try to help your mom get the help she needs, please.