Okay, right, validate;
I do similar things with people; make assumptions that I am not liked or that they purposely ignore me. I do that a lot at work actually. Really its either nothing to do with me, they are annoyed in the moment or are consumed with other thoughts and don't even know I might feel ignored. I try to remember this, but unfortunately I have a bit of a name for myself I think. People get annoyed that I am like that
Really though, I can't imagine anyone not liking you. First impression be damned, everyone knows that first impressions don't count. Its what the person is like as a whole is that matters. If she doesn't know that then she's an idiot. I know she isn't, so I still air on the side of her just living her life and not being concerned about you as a friend at all.
She's pretty casual at the best of times no? Her ideas about conducting relationships any way. You are just different. That's what I think anyway.