Wow - I don't have much sage advice here. However, I do agree that you have absolutely nothing to apologize for. If W sees this as her out - LET HER GO! I believe wholeheartedly that this sitch caused your D14's acting out behavior. Refresh me - does D14 see a counselor? Your girl's need someone who can help them understand why your W does/says the things she does and why it isn't their fault. Whether W goes or stays you need to continue protecting your girls and you need to be sure that they know they are loved and cared for and that their Mom's issues are not their fault.
I cannot help but think that W's being out of the house might be the best thing. Have you ever considered a "trial separation?" while W gets hold of herself and her behaviors. Sometimes this is advocated for people who have addictions and won't stop - the family is advised to physically separate and to set certain boundaries. This is not a "legal separation" and fidelity is still expected but it gives the people space to get hold of themselves in situations that have become dangerous.
Regardless of what you decide VB - you are good man and a good Dad.
