My best friends cousin came into the States when she was 17, she was super sweet, complimentary and always asked me to do her make-up and so on.

I saw her true colors when we went to a party back then. As soon as she saw the guy I was casually seeing, she made it a point to flirt with him and she requested to follow him that night. From there a pattern emerged, I wasn't dating formally so I would go on many dates and anytime a guy hearted my pics or commened I would see how she followed them almost instantly.

She questioned me at times why I didn't have a boyfriend if I had so many guys interested in me. She also asked if I wasn't afraid to get a rep as a slut do to me dating different guys. Thankfully the times I didn't speak to her often but I would still find out she trash talked about me. I always saw her as a child so I never paid her no mind.

Fast forward, she's now 22 and started living with my bestie and her younger sister. My best friend and I are really close so I spend a lot of time at her apartment. Last night we had movie night with our boyfriend's and sure enough she was trying to flirt with my bf. She put on these little pijama shorts and a sports bra and sat down with all of us even though no one invited her and just right now he showed me her follow request. And get this! She had liked 2 of his Facebook pics back in May, he just didn't know who she was

Now I'm in no way threatened by this girl, I don't really care gor her either, but I'm wondering if now is the time to say something, since I will for sure have to interact with her, while in the past it was easy to just ignore her.

This is more of an annoyance, I don't feel insecure about her whatsoever but I feel like just letting it pass will make me seem like a pushover, plus I really want to draw some boundaries. I just don't know how to approach it without giving her the satisfaction of thinking she's a threat to me.