I don't know how you inform the misinformed. How do you convince a stubborn person they're wrong?
As Danny has noted - how you manage this starts with you recognizing that the issue you have to deal with is not "misinformed". It is not "stubborn". The issue is more, "has a different belief system". You are engaging in bringing a person to choose to change their fundamental beliefs, the axioms upon which the assumptions of their lives are based, and their decisions made. That is a tall order.