She may not be open to the idea, but she might benefit from rehab. I have a friend who– after years of suffering from major depression, suicidal tendencies, and substance addiction– checked into a rehab facility that focused primarily on mental health, and it helped her a lot. They placed her in a house with seven women in similar situations, spent a lot of time doing therapy, and taught her healthier coping mechanisms.
The biggest problem is that your wife will only accept help if she is ready for it. If she isn’t in a state of mind where she wants to get better, she won’t. But a rehab program like the one I mentioned might give her the initial motivation she needs.
Take care of yourself. Reach out to her friends and family to help you. You are not alone, and you shouldn’t take on the full responsibility of getting her better. Try to find a few other people to help you, help her.