Ok.I can totally relate but I was wracking my brains for some useful advice.
What I was thinking was that as you rightly said what has got you this far is your hard work, brains & family help. As you continue baring most of the load and pull through whatever issues arise hubby will no doubt put that down to Jehovah too.
The only thing I could think of was to find a decent financial advisor of some kind ( the free kind that come with your bank or better yet a paid proffessional if u can afford it) and put your cards on the table. Tell them everything. The reason you are in this situation, that your husband can be relied on to a limited extent only and what you want.
See what they can come up with, a life plan if you like.
I really wish you all the best, beautiful and talented, you go girl!