I don't know the history between your BF and his friend, but in my case I've been best friends with the same guy since we were little boys throwing rocks at girls. Some old habits die hard. When we get together we're every bit as obnoxious and immature as we were in those days.
Some of the girls I've been with don't like that. A girl I once knew gave me an ultimatum, "him or me." Note I said girl I once knew. Be very careful when dealing with your BFs friend.
God, so atrocious in the Old Testament, so attractive in the New--the Jekyl and Hyde of sacred romance.
-Mark Twain
If people are good only because they fear punishment and hope for reward, then we are a sorry lot indeed.
-Albert Einstein