Assexuality

Hey! So, I have a friend who says she's bissexual, but thinks that she's assexual for women but not for man.
She says she feels sexually atracted to men but not to woman, and that she had a dream in wich she was kissing a woman and that thought disgusted her.
I wanted to know if anyone thinks that this is possible? Like, if you can be assexual for a gender but not for other.

P.S: English isn't my first language so I'm sorry if there's anything wrong!!