Ok, I would tell her before she goes to her families place and not like 10 minutes before either. She deserves to know, and she deserves it be told in a respectful mannor. Over the phone would be extremely harsh. Telling her while she is at her parents is also harsh. Imagine that it was you, how would you like to be told? If you do this while she is at her parents that could be humiliating for her, and not give her anytime to regroup herself.

You can't just show up at her parents with a friend run in and tell her you are divorceing her and then take off. She will likely have stuff she needs to say or ask you. Yes she has problems but she is still human. She is going to her families house so hopefully she will be safe. I guess just think about how you would want this handled if it were you in her position. It's not easy to tell someone you want a divorce, I know that. I wish you luck and I hope your wife will hear what you have to say and remain safe. If she hits you you can leave. You cam call someone for help.

Sometimes we underestimate our partners. I know for certain that my boyfriend used to think I wouldn't survive with out him, or may harm myself if he ever left. I ended up being the one who broke it off, and I was ok. I was strong even tho it was hard. I have mental Heath issues and previous suicide attempts as well. My boyfriend who does not have these issues was not ok tho, I still offered him some support and let him know that if he wa going to do anything harmful to call me, I would help him get help, not get back together, just help because I did care about him. if he had called it off, I would not have harmed myself, despite what he may have thought.

So just do not under estimate her ability to deal with the situation.