I've just realised The Girlfriend is the friend. Not read it all sorry.
I just wanted to say, I had a best friend who was a bloke. His ex-girlfriend disliked me. I didn't let this bother me, until a party we both attended. She started having a go at me in front of everyone, and made some horrid comments. She was vicious. I stood up to her, but my DH (boyfriend at the time), was not around to come to my defence, and my best friend just looked at the floor. I had to walk away from it, left party early, and balled my eyes out all night.
I didn't speak to former best friend for two years after that. He did split up with this girl, and it was very messy, as they owned a house together. He now has a lovely girlfriend, a much healthier relationship, and they both adore each other. We made up, as he contacted me after the break up, to make amends. It's never been the same closeness though, and we are now more like acquaintances, who share some of the same friends.
The fallout was awkward, as we were part of the same group of friends.
My best friend, cheated on his vicious ex-girlfriend lots. He used to be a male tart. We have known each other since teenagers, never kissed each other, only ever been friends. There was another friend of his, who his girlfriend adored and got on with like a house on fire, and he regularly slept with this other friend. I never approved of his cheating, but as we were such good friends, chose not to fall out with him over it. I always knew he'd split up with his ex-girlfriend, as they were like chalk and cheese, and had completely different outlooks on life. The only thing they had in common was that they were both good looking.
When she had this huge go at me, I wanted to list all the girls he'd cheated on her with, but held my tongue.
He's apparently faithfull with his current girlfriend, and none of us have heard of any indiscretions.
P.S. I learnt after the fallout, that the reason this girl disliked me, was that she felt me and her boyfriend flirted (I think our familiarity with each other could have been considered flirty), and she picked up that I disliked her. I did dislike her, as she was negative over everything, always scowled at me, and insisted on having everything her own way, with my friend. She was extremely bossy with him. She wanted a different man, to who he was, and tried to boss him into being this man. She never realised he cheated on her.