YANBU to be scared, but you need to take a deep breath and start taking baby steps to start getting back on an even keel. But first, consider the worst, the terrifying bits that you're trying to hide from at the moment. From your post:
you might lose the business, the house and your settled family.
This might still be the case even if you fight hard for it not to be, but at least you will have tried everything. If you do nothing then, from the sounds of it, it will be the case.
As HighBrow says, start planning. Questions you might want to consider are:
Where do you want to be in three years time?
What will it take to get there?
--->If the house and community you are in is good, then maybe a couple of hours commuting a day is do-able in the short term to stay where you are
--->Will the bank consider helping with injecting finance into the business?
--->Is there additional government aid available for childcare/small business/re-training?
--->Would a minimum or low wage part-time job done during the evenings help keep you going until the 'recovery' starts to trickle down from the financial markets into everyday life?
---> Are there any agencies that offer contract roles in your old industry to get a foot back in the door? Or even in something else that you would be able to do, even if only reception/admin cover in an office?
If you can take that first step, you will get there. You built a business once, you can do it again.
Also, yes, I know several people who ended up with a long-distance commute so they lived abroad and sent money back. In one case it was a weekly thing, and home at week-ends, in another they got back once every six months and carried this on for three years until they were on a stable financial footing again. It wasn't easy on anyone, but they managed because they knew it was the only way to keep what they had built up prior to losing jobs.
Best of luck and hope your life manages to turn for the better soon.