It can be romance partner , family. this has been my personal experience. I'm cheating is very much one of toxic relationship , another toxic friendship I did have twice with two female was friends for my first ex boyfriend from college. My last ex boyfriend was must toxic person ever. yep he was one that has a lot of trust issue and was very sexiest. he is very immature. they no point of helping people. I know they some people can very good at hiding their true self. It anything else you can add.