SalP:  I agree that you guys should avoid friends.  We try to even avoid becomeing friends with the guys my wife relaxs with although that is hard.  Mixing friends and your sex life can be difficult, unless your fine with everyone knowing about all of your life.  
Also avoiding becoming friends will keep your wife thinking it is all sexual instead of starting to feel like she is in a relationship, like many girls feel they need to have sex with someone.
You have been here awhile SalP so I'm sure you have heard this before, but women like to make sure we are serious about all of this and that we don't have alterior motives before they will truely admit they are interested.  It really sounds like your wife is close. .... 
