I guess I disagree from the others about the insurance (though agree with the other statements).
You are legally married, how long does a D take (talking worst case scenario here). As far as I know, even with a legal separation, usually the health insurance benefits are maintained until the final disolution. As his wife, you are entitled to the insurance and I don't think you are doing anything disrespectful by using his insurance.
He wants you to take care of your own problems, than I would do so without his input, do what you need to do for you.
I wouldn't send the email and I wouldn't feel the need to tell him what measure you are taking to secure your own mental and physical health.
