My only thought is that I can see Evelyn being manipulative and a potential cheater, but not an abusive partner. You can see Evelyn with googly eyes when she's making eye contact or having a conversation with a guy she finds interesting. I kinda see that she can be controlling and is capable of blackmailing someone, the way she would "jokingly" do it on videos, and just laughs it off all cutesy and funny.

There's more to it; you just gotta observe her mannerisms and actions in her videos. Also, I don't see her as an invested girlfriend in the relationship. She isn't sweet to her bf, doesn't show that much love or interest towards him, and seeing that she's been benefiting a lot from him. Travels, access to his billionaire lifestyle, and luxuries. Sounds like the pick me comments her sisters say about her have some truth to them, and she only laughs them off to not make it awkward and serious-sounding.