When they are together in public, you give the cut direct to both of them. But if you have a good relationship with the wife, I don't see anything wrong with socializing with her separately one on one or in a situation that would naturally exclude her husband, like a girls' night.
I didn't give him the cut direct but I did not care for a friend of mines boyfriend at all. When I socialized with my friend, it was only the two of us. I might have seen him in passing while picking her up but I made sure that any plans we had involved minimal contact with him. She knew how I felt and never tried to force the issue. Fortunately, she broke up with the guy and is now happily married to a nice guy and they have a 6 yr old daughter.