help for a greenback

Hello, i've just joined and would like to get the advice of you veteran's out there. I am not a nurse--not even close. I used to be a graphic designer in New York City (designed children's books) about 10 years ago. i've been a stay-at-home mom and homeschooler since. Now my husband has left me and am 50 years old with 2 girls (7/12) and am trying to decide if i would like to pursue nursing. i really need to have the job security that nursing seems to offer. i only want to work part time in a job that is not extremely stressful. Is this possible? I also have developed a degree of fibromyalgia that would limit me working more than 4 hours per day, but I seem to be tremendously helped by physical activity, so I can't work a sedentary, computer job all day.
ALSO, I have a B.A. Where and how can I get started? Which degree will give me the most flexibility? Can I do the fast track online?

There!! Let me have. . . thanks