It sounds as though you've built a great relationship with them, hopefully mine will grow up to be the same. I want to have an open and living relationship with my children, here's hoping I get there!
Heidi: Our children were even older, adults, but still at home. And eventually knew everything. I think they had more or less guessed anyway, but as time has gone on, they have accepted things and have been an unintentional source of support too. They have asked questions, vented their feelings and I have never tried to put my feelings into their heads. What they say or do is completely of thier own volition. My son in particular once said that an affair wasn't a way out of problems in a marriage, and it would have been better for his Dad to have talked about it. And my daughter once said that she was glad she knew because it was a relief to stop worrying about things.
We are all very open about things together and can talk about the affair, and I know that should he want to talk to them about it, they would be quite open with my husband too.
I agree, it is our job to bring our children up in the best way we possibly can and to arm and equip them for whatever life may throw at them. The whole idea is to learn from other people and the mistakes they may make.
We all love our children dearly and like you say would do anything to protect them from the trials and pain of life somehow, because having learned it already, we know how certain things can feel. But it isn't possible or practical to do this. At the end of the day, you end up with a much more well balanced human being. You put it so much more eloquently than me...