Hi DDees, thanks for this question -- so many people have similar problems, hopefully the answer will help a lot of people.
There is some help available from the federal government but it's a little complicated. Money is awarded to states in the form of Block Grants and some of it is used for home repair and rehabilitation. There is also a new non-profit created by Congress designed to help folks like you and build up strong communities.
There are also more non-profits like "Rebuilding Together" which you could search for in your area. They provide repair services for seniors and those with low incomes and might be able to help you (though a slab might be beyond their capabilities).
Since your repair will cost more than $5000 you might qualify for a specially subsidized loan or, since you own your home, you could take advantage of an FHA loan designed to combine home repairs into the amount of a refinanced mortgage. And the U.S. Department of Agriculture also might have a program for you depending on where you live.
Bottom line: you have options! You can get more information and guidance on how to find assistance in your area here.