"People don't do things to you. People just do what they do."
This person was saying it in regard to the way his alcoholic family member kept hurting the family and his struggle not to take it personally.
If I could remember this for myself each time I offended by someone I could be a much more patient and loving person. When someone snaps at me on the subway or a friend or loved one has hurt me, these things are usually not personal. They have far less to do with me than they do the heart of the individual who is acting out. And my reaction can either feed their anxiety and continue a cycle of negative responses. Or I can choose not to take it personally, not to worry about my bruised ego and move on.
People don't do things to you. People just do what they do.