I can relate. I was in a field that I could succeed in, could make decent money with, had potential for much more money. I was pretty good at what I did. But I had no passion for it...and maybe my problem was more that I disliked it. But I left and now I am a starving artist.
I am pretty sure that doesn't help you at all, and I have probably told you that once before, but perhaps you might avoid leaving a career that feeds your family for all the uncertainty you gain without the old solid income.