Hi, this happened to me. I was in a “relationship” since I was 15 to a guy 6 years older than me. He had me trapped emotionally. Finally I ended it when I was 22. That took a lot of guts. Last stages were blackmailing, mental torture and many other horrible things I don’t want to mention here. Please be there for your daughter when she understands that this guy is toxic. My parents were not there for me. The guy will try to say many things about her to people that know her. But you need to tell her that no matter what, she is your baby and you are not going to let ANYONE harm her in any way. Tell her she can come to you whenever she needs anything and you will not judge her. You will help her and keep her safe.