Friend is forever flirting with fella

I'M sick of my mate flirting with my bloke.

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She texts him saucy jokes and meets up with him behind my back. They both swear that they've never slept together ~ but how can I believe that when I've been fed so many other lies during the past few months?

My fella and I have an unorthodox relationship. He lives in a flat share with three other blokes, because he loves the party atmosphere and the banter.

He says my place is too neat and tidy and living with me would drive him round the bend.

We see each other about three times a week, but I always contact him because he’s not much of a communicator. I drive him to bars and clubs too because he lost his license through drink driving and I don’t drink at all.

He's never said that he loves me, because he’s not like that, but we do have a good sex life and I adore him. Unfortunately, so does my mate and I'm beginning to feel increasingly intimidated and threatened by her.