Am I overreacting? My flat mate is driving me bonkers!

I'm married with 3 kids and we also share our house with my husbands work supervisor and he's currently sleeping with my sister in law who has moved in with him. But there are times when I feel that she is really pushy the relationship and I don't mean just with the guy but my husband and I as well.
We introduced her and the supervisor and they hit it off pretty quick and when he wanted to move we offered downstairs to him. We didn't invite her and she didn't ask, when I vaguely asked the guy how things were going he said they she's moved all her stuff from her old place to here without really asking.
She comes upstairs when we're not at home and uses my computer, last month she watched so many youtube videos we reached out download limit half way through the month!
She drinks quite a lot and when she does she's a real drama queen. I can understand she's been through a lot in the last year but the dramatics are really ticking me off. She can be quite unreasonable to the guy and I feel a bit responsible because we introduced them.
She doesn't pay any rent to either the guy or us and sometimes I feel like just telling her to pack up and leave! But she is my sister in law and my husbands favourite sister at that. She's a real mummys girl and I don't want to create any problems with that front either.

Sorry about the longwinded story but I really don't know where to go from here.
By jemima 8 years ago :: Roommates
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