1st Corinthians 15:33
KJV:Be not deceived: evil communications corrupt good manners.
Jesus is the perfect and best friend any man could ever have because he is true to his words and has nothing deceptive about his ways and dealings. Jesus' friendship should be our standard for selecting our friends. A life that is good of the God is enough to drag is to the pit, it is therefore requested of us as Christians to watch our company because light and darkness have nothing in common. No matter how spiritual a person appears to be,if he has not yielded his/herself to God, then he can easily lead is astray.
It may be so painful to loose a friend but it is more painful to miss out of eternity with the king. the benefits you get from associating with friends who has yielding their lives to God can never be over emphasized. You can find a prayer partner, an accountability partner, a mentor, an advicer, a helper on a friend with the mind of Christ bit you can never find that on a worthless friend ..
Be wise in your choices of friends.