Date after divorce with a narcissist

How can I date someone after a divorce from a man who is a total narcissistic control freak?

We’ve been divorced for several months now https://printabledivorce.com/texas/galveston-county-divorce-forms/. I’ve been talking to a really great guy for about a month and now my ex-husband is literally threatening this guy’s life if he keeps talking to me.

This guy is very sweet, so obviously he doesn’t want to get involved. I told him that I fully understand and respect that.

Someone tell me how to deal with an ex like this. He can’t control me forever