<human>: Okay we broke up about 3 months ago, it was a pretty mutual breakup. Nothing bad happened, just knew we weren't working and we decided to end it. Went no contact but we always run into each other on campus since we work in the same building. Everytime we do run into each other we both speak and sometimes catch-up with small talk. About a month ago we tried to be fwb..but it didn't work for obvious reasons. Ever since the break up she's been treating me pretty badly when we were in contact for whatever reason. Of course, I don't blame her--she's just trying to move on. But now she is COMPLETELY deliberately avoiding me. As far as moving to the other sidewalk when she see's me on campus. I haven't done anything to her but be nice every time I see/talk to her. I don't contact her so it's not an issue of me being a crazy ex. This has seriously come out of nowhere. The first couple of months after we broke up she would come talk to me, text me and tell me how good I look, etc. But now, just in the past few days she has this sour look on her face if she does see me and then proceeds to walk in a different direction.

 I want to contact her to see whats up, but I know I won't get an explanation so I'm not going to text her. But seriously, have any of you been on either side of this? Can you explain what could possibly going through her head, from one day seeing me and telling me how good I look to a few days later avoiding me at all costs.

Could you distill the essence of the text into 1-3 sentences?
<bot>: Ex went from being civil/nice every time we run into each other to completely avoiding me when she sees me for NO reason. What is going on??