It sounds insensitive, but those with a victim personality are actually quite clever. They may not realize they are doing this, but they would use their horrible experiences for gain.
Victims have a long list of grievances and would use any willing friend to dump them on. They would want sympathy and undying support in return, and a whole lot of attention to boot. In fact, they may even exaggerate past injustices in order to gain free rides in the future. For instance, they would expect you to do all the work in a project because they’re upset about their relationship.