Comeback advice: how to return a decade after dropping out, when job schedule makes formal study difficult? What helpful advice would you give an age 30-something woman to reach her dream with the following background? She dropped out from college a decade ago despite many hard years of dedicated trying, had to take on a low income, shift work job to earn a living, but never stopped to want to make a comeback in the demanding major where she dropped out and participate in science where her heart belongs?

The shift work prevents her a lot to get up to date again and prepare for college and nobody supplies support against her worries of failing again.
Get connected with a support system.  Places to look: organizations with names like "women's opportunity center", campus women's organization, etc.  Community colleges are a great initial re-entry point, even if you are going to re-enter as a junior or senior.  Just take a class or two at a good community college to get your feet wet again, and because they are much better at integrating "returning students" like you than most 4-year schools.

If you have any specific questions please ask so I can give you more specific answers.

Note: my Calculus I teacher went back to school in middle age.  She was one of the best teachers I ever had.  And this was at a community college!