Does she still like him?

My best friend went out with a guy in our friendship group for 4 weeks. My other friend is in a long relationship with another guy in the group, and they get on really well. My best friend, well, clearly is jelous of their relationship, and kind of rushed her 4 week one and then started to blank him as our other friend didnt really approve. So he started talking to me more, and then she started accusing him of liking me and visa versa. I kind of ended up starting to like him. Its been 4 weeks since they broke up and I'm contemplating asking him out. She insists she doesn't like him, she wont even talk to him anymore, she says she hates him, but I told her sister that I might ask him out and shes like "Dont you think that'll upset my sister?" "To be honest that would be a betrayal of her..." When I told my best friend I liked him she didn't say anything. Do you think she still likes him?