I think this is probably the best approach. I would be tempted personally to mention divorce but I think this person is onto something. This is the first course of action. Of course if she's not engaging then I think you will need to bring up the topic of separation/divorce and if she still wants to be in this relationship.

Because you can't fix this alone. And living like this is a poor example for your child. Seeing his mom avoid interacting with dad and repelling at even the slightest touch is a horrible example to be setting.