I'm really glad you had the self-control not to react when your wife said those things. I think if you ever feel you need to say anything it's probably okay to say, "That isn't true." But then do not say anything more after that. Stay quiet and composed and let her rant and rave. I've learned that the person who can stay calm, reasonable and rational is the one who comes out looking best, while the one who "loses it" almost always comes out looking worse.
One more very important reason to tell the kids the truth about the situation is children tend to see themselves as the center of their universe and it's very common for children to believe that the reason a parent left is because of them. That they did something wrong or bad that caused a parent to leave. Even kids who don't verbally express that usually have those thoughts floating around... and anyways, what's done is done! They know, and she'll just have to live with the fact she's a liar.... oh well...
I think you are doing well in spite of everything. Just keep GALing, and stay as dark and non-confrontational as possible while your wife is in angry-mode. You will need to accept the fact you have no power to "fix" your children's lives. About the best you can do at this time is to be the "Disneyland dad" and when they are with you give them lots of love and great memories. And when they aren't there... go live for yourself.
There is no arriving, ever. It is all a continual becoming.
