I feel your pain. Transitions and self-reinventions are the hardest challenges to face and endure. Do not despair. As you watch over your children, you can take this time to think through the next phase of your life. What are your passions? What do you really love to do? What are you good at? And if you needed to go back to school, you can do so part time--whilst watching your little ones. One thing I did is took a few classes to see what really turned me on--got me going. Then, I would also talk to people in various professional fields to see if that sounded like something I wanted to pursue and do as a future career, long term.
This transformational journey is organic and requires tremendous patience. I know one thing, however, your kids will grow; they will lead their own lives sooner than you think; and having a passion or profession that you can call your very own will be paramount to your well-being and full self-actualization.
You are very talented, with great skill sets. I'd love to learn more about what you love to do and what you're good at.