You did fine doc. She just doesn't want to deal with the consequences of her decisions. Be careful with her family...they may be sympathetic to you now, but she will always be their blood.
Antidepressants help a lot of people through these situations. In your place, I would keep that information from your wife. Even though it has no bearing on your stability as a father, you don't want her trying to make an issue out of it.
Has your wife always been so sneaky/manipulative, or is this a recent development?