Your Husband is living a lie. God would NEVER tell him to "not be married" ONCE he has made vows to you. This is a lie of Satan and I pray that God opens his eyes to this. He is being deceived. My dear sister in Christ, you need to stand firm and fight against this evil. I am sorry but I find his relationship with your sister out of line and not appropriate and I pray that he has not stepped over any boundaries, although I feel he might have. I pray that our wonderful God will grant you comfort, wisdom, courage and determination to walk forward in the future. AMEN.