Know what you can be thankful for? That she's leaving the kids with you. Custody is pretty much assured for you. If I were you, I'd get into the mindset that I don't want her back. What's to want? Try it on for size.."I don't want her back anyway, so who cares what she's doing." Perhaps she'll make great strides to improve herself and earn her way back into your life...but you can afford to have an attitude that makes her win you back, rather than waiting for her to hit rock bottom and then come back to her knight in shining armor.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer