The way to get around being an ex-boyfriend is to never have been a boyfriend in the first place. In other words, never date a person, especially a female. You never really know what another person is going to bring to the table in incorrect fashion. I'm serious. Don't talk to people. Leech off them if you must, but never make contact with people, not even a hello. A hello invites them into your space to take advantage of you, which humans are prone to do. Go far away from them because they surely want something.