What you are God's policeman? God will decide not you. Stop bearing false witness.
When a person departs the truth of the Scriptural description of the Gospel for the errant, demonic doctrines of Rome, it is the Scripture who says she has lost her way...not me. Actually, the Scripture makes it plain that God has driven her away. You may not like this uncomfortable fact, but take it up with God (Rom. 9:19ff). Grace to you, my FRiend.