Alan. I feel for you mate, try not to let this experience destroy you, and make sure that your kids know one way or another that you love them to bits, it's not only you losing the kids, it's the kids losing their dad.
This is a good thread and also a reminder that marriage is a bit like a WFP system, the time we put in on maintenance and improvements pays off, either we change filters, flush membranes, check TDS, buy flowers, and all the other little things, or we pay huge bills when the system fails.
A good partner is worth her weight in uranium, I tell my wife this every day, I mean it too, I wish she would leave all the 25 litre containers she fills a bit closer to the van though.