The feeling in your gut can be the holy spirit letting you know you are being lie to. Sometimes God is talking to us and we refuse to hear it, unless something hits us in the face like a bat. If you can't trust this person just leave them to God, and keep on your path and don't have anything to do with them. God will give you the strength to do so if you allow him, but not if you keep yourself stuck in the mud.
Lord have your perfect will done in this person's life and the situation they are in. In Jesus name I pray, amen.