If you discover someone is using you and you decide to cut them off, do it for you. You deserve better. If you think you are cutting them off to “teach them a lesson,” there is probably no lesson for them. Some people are users. They believe they are entitled to your kindness and generosity. There will be no guilt, shame, or bad feelings going through their head about taking from you. Eventually they will find another person or charity to get whatever they can from them.