I am so sorry! How old is your mom, and how old are you?
Is your mom currently being treated, and are you able to go with her to a doctor's appointment? Are you able to talk with her doctor about your mom's mental health, and ask for a referral to a counselor? If she has lost her will and desire to care for her own health, it is time to seek professional help.
First of all, have you talked with your mom about your concerns, and mention that you care about her health even if she has lost faith right now, and let her know in advance that you would like to speak with her doctor.
We can help find resources, please let us know how we can help.