My friend and partner are currently facing a ton of marriage problems, it is very likely they will divorce but non of the two has brought it up yet.

Despite all that, his wife says now that she's in her 40s and they don't plan on having anymore kids, the guy must have vasectomy done, he is clearly against that but she won't stop insisting.

It's the first time I've heard such a crazy request.

How should my friend deal with this?