I want to know some opinions on this:

One of my work friends arrived in the morning today and I said hi from across the room, but she ignored me. Then she went to sit across from me with the girl who bullies me, and said hi to HER and asked her how she is. I said hi again, to which she finally responded but only with a slight wave and arching of brows...
...then when I suggested we go check the machines as we usually do when we arrive, she gave me sort of a cold response. The office was so quiet... I felt very embarrassed.
The girl who bullies me noticed all of this and was extremely amused.

...I'm not sure what it means. She's fine on text messages. I'm not sure why she did what she did in front of our colleagues.