You can talk to your broker and see if he has anyone looking to make interest on your deal or if they have a hard money lender that will step in and help you out. This type of loan will get your home done so you can get it refinanced into a more conventional loan, and get moved it.
Your lender may have defaulted, but your contract with the builder is still in place. Your liability with the defaulted lender as well as with the builder is still in play. You are able to negotiate with your builder at this time and you may be able to walk away from the deal altogether. BUT, you should consult an attorney for the best advice.
If you are building on your lot, obviously that is a huge difference. In either event, I would first contact an attorney to find out what your rights are & proceed accordingly after that advice.