Bad friend behavior?

Please feel free to tell me that I’m being unreasonable or overly paranoid. I’ve got a girlfriend who seems to relish being the other woman, has no qualms whatsoever about being with married men or men in committed long term relationships. She also has a real love for being a martyr, and letting men treat her terribly. The other day, she was supposedly having a Halloween party. I show up with my newish boyfriend who I’ve been incredibly hopeful about, and first she answers the door in lingerie. A slutty Halloween costume to the extreme. And she was definitely showcasing assets that she knows I’m terribly insecure about lacking. She knew going into it that there may not be any guests besides myself and my boyfriend. We’re in the Northeast, and it’s cold. Should have said that sooner. Anyways, it’s just the 3 of us for a couple of hours, and she’s essentially in lingerie. She starts weirdly focusing on random little ways that she’s compatible with him in conversation. I am always cold, especially in my boyfriend’s home. I’ve told her about this, just as two girlfriends venting innocuously. She starts telling him how she’s always warm – unprompted. They bond over this for a few minutes. And I had recently told her how much I’m miserable – as he runs hot and keeps his house unreasonably cool. She stayed on this bland topic for way way too long. Little things like this continued, with her seeming to jump at any chance to show him how much they have in common. My boyfriend did wonder if she was having ulterior motives, especially considering nobody else showed up to this so called party. I can’t help but question her motives. Am I being crazy? What do you think?

Sorry to say but I think you need to be a little weary of her, don’t worry a lot about it, just keep an eye on her. if she thinks it’s ok to have relationships with married men or men who are in relationships then she doesn’t sound very trustworthy. She probably has very low self (and a few other issues) esteem herself, and this is why she acts like this and allows me to treat her badly too. Trust your instincts, if your bf picked up on it too then it’s not just you being paranoid. Not if you look at what she’s done, pretending to have a Halloween party where no one else turns up, dressing provocatively and trying to see if your bf has any interest in her. There’s a reason why she’s done it and she’s done it before! I would stop talking to her about your bf and relationship now, don’t give her information. Be on the look out she might have another ‘ party’ or want to hang out with you and your bf. So make sure it’s just you and her. BUT I think another question to ask yourself is how much of a good friend is she really? she should be happy that you’re happy.

Thank you. I agree, and I am going to take your advice and stop giving her information. I guess I thought I was an exception because we're old friends, that she wouldn't do to me what she does to strangers. Of course the cheating guys are the worse ones, but yeah - I've told her many times that it's ugly behavior and just bad for the soul. I appreciate your thoughts!