The term better off without you means that someone is in a better position when you are not in their life. If you betray someone or you make their life more difficult in any way then they may not want to continue associating with you. If someone is better off without you and you truly care for them then you will want them to have a good life. Some individuals are destructive, and they tend to hurt or damage others around them. If you are this type of person than others may be better off without you.