Dude, the trick is to GAL for yourself not for her. No one ever said you would win her back for sure. But you have to sort you out and not always looking over the shoulder what she is doing... Frankly what ever she is doing is none of your business as long it isn't interfering with your life or the life of your kids. So let her go and let god.
And when you learn that you will be just fine by yourself, that's when growth begins and that's when wonderful things start happening...