Okay, so I did so so in high school. just over a 3.0. I entered the work force, doing things one does without a degree, and eventually enrolled into a community college. My grades, including math, were much better this time around and I transferred into one of the nation's top universities.
My advice? Take things slowly; but, give it a try. Here's how I'd do it if I were you. Go to school part-time. Take one class at a time if you are working. If you are not working, don't take on anymore than part-time course work. This allows you to have maximum time to do well in those courses. No one will care that you went part-time, they will care about the grades.
You also might consider starting with a CNA. That's what my ex did while she was in school. She had work and graduated with experience. The Red Cross offers a four week course for $1,300.00. You may check if a community college offers it and if you can get financial aid as well.
I found reassurance in my path from a surprising place. I'd recommend listening to Jim Carrey's commencement speech at Maharishi University: https://www.youtube.com/watch?v=p6LW9US9QoE.
It's incredibly inspiring.