Would a girl do this to cover up?

Ok, me and my crush sit with another girl and they were snickering about something. My crush knows I like her and the girl I sit with tries and helps me out. My crush was like "Soo would you rather date him or become a lesbian?" and the girl said "Definitely him" and my crush said "oh..well at least you've got one going for ya". The next thing she asid was "oh when she told me that (meaning when my friend told her her I liked her) I started twitching and my self esteem just plummeted. (She does this knowing it bugs me I think because she's actually usually nice) So does she say this just because she doesn't want to admit it, or is it because she really feels that way? I find it hard to believe that if we are friend she would be that cold though if she was telling the truth.