So he’s ruining his life, so what?

One of your staff/friends/acquaintances is ruining his life.

So what?

Maybe he’s working too hard. Not spending enough time with family. Not exercising.

It’s none of your business.

Your job is to make sure your staff are doing their jobs whilst creating an environment where people can see their family, exercise, etc.

If your staff choose not to balance their life, it’s not your problem.