Had to kick Boyfriends Best Friend out...?

[CuriousGirl]

Okay so here's thing my my boyfriend and his best friend moved into my house with me... Everyitme I walk around my house in my boyfriends hoddie and a pair of shorts his best friend always comments on the fact that I am flauting out relationship... So I had talked about it with me boyfriend and we sat down and talked to his best friend... I thought the air had cleared but my boyfriend was sent out of town for work... After two days of him being gone his best friend came up to me while I was sitting on the couch watching t.v and sat down... which I didn't think much of... I mean yeah he has a t.v in his room but if I'm watching osomething he likes then whatever... within two minutes he had his hand on my thigh and told me that is was okay and he talked to my boyfriend about it and seeing as how they share everything that he could have me if me wanted and he decided tonight was the night... Anyhow I asked him to leave and he did but now that my boyfriend...
is coming home tonight and I have to tell him about... His best friend has stopped by to grab things and told me that I screwed up because my boyfriend will never believe me over what he tells him.... Any advice on how to approach this with my boyfriend would be greatly appreciated... Thanks in advance...