You have a lot of great suggestions on how your father should and will provide money to support your mother. However, that still puts your mother at the mercy of the courts, lawyers, and/or your father's generosity.
Even if all that works out and your father is really into helping your mother financially, I think she should take this time to look into other work options to help herself.
If anything ever happened to your dad, she shouldn't be in danger. Plus I really believe there's something important for your self-esteem to work and have some control over your world. If she's going through a divorce, it would be good to have control over something and make some friends.
I know you said she has health issues, but paid work can take all kinds of forms. There are lots of work from home / virtual admin. jobs, medical transcription, call center jobs, after school tutoring, part-time work. I'm not sure what restrictions she has, but she may want to look into what she can do. There's time now for her to take a class online or locally to get any training she'd need to do something she'd enjoy. She could add that to her jewelry money, or use it to expand the jewelry business.
Again, I don't know all the details of your situation, so maybe this isn't possible. I'm just thinking it might help her spirit to be doing something. If she's able to make jewelry (focused work for a short time) she can stuff envelopes or other things. Keeping busy, being productive, and making friends could be very good for her. I hope that helps a little.