Should I be jealous of my boyfriend's female housemate?

Basically me and my boyfriend started dating in October last year. We had been friends for about a year before this but I had a boyfriend so I never thought of him in this way. Between October and December we were having a great time, we both met and got on with each ocher's friends, and were v compatible, However over Xmas break I found out that he'd been talking over Facebook to a girl he works with. He admitted to her that he fancied her after she told him she fancied him, but because of me, he wasn't interested in doing anything about it.

I was upset but he reassured me he didn't even mean it, he just felt awkward and didn't know how to handle her throwing herself at him. We recovered ok from this, but sometimes I do dwell on it a bit. The next month, he tells me that he is moving in with a girl he knew from his first year along with 2 guys from our course. The only thing is when me and my boyfriend were just mates he had told me that he had had a thing for this girl and that she was 'messing him around' (apparently nothing ever happened)

I agree to a night out with them, and all night she does not try to hide the fact that she doesn't like me and is flirty with my bf. I snap when we get in and tell my boyfriend that if he does move in with her, I will refuse to go round to his house or have him at mine. He signed the contract anyway, despite telling me that if the situation were reversed he would hate it. He didn't help matters when he went and told this girl that I didn't like her. (her reply was 'not many girls like me')

Please help. I don't want to lose my boyfriend besides this he is v caring and loving, but I can't stand the jealousy anymore. He tries to reassure me he doesn't have any feelings for this girl but it doesn't seem to make a difference to me. What would you do? Btw please be honest if you think I'm being crazy.
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+1 y
turns out he did like her. he got me pregnant, found out, dumped me. he left me to get an abortion by myself, with not even so much as a text to find out how it went. he's now sexting her. I hate men
Should I be jealous of my boyfriend's female housemate?
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