Hi MC: Just as others have already said, keep the focus on you and the kids. No one is responsible for what goes on in your W's mind other than your W - and she will have to come to terms with her actions at some point in her life - but that's not up to you anymore.
It sounds like you're doing a wonderful job for the kids - keeping things together in an impossible situation - and making sure that they get the kind of love they need.
I've thought sometimes about writing a letter about the situation to my W - but I don't think she's in a place to process it - such a letter wouldn't be about her - and these days everything seems like it has to be about her for it to make sense to her.
