Need your opinion about a situation. She avoids me as if I’m carrying some illness.

First of all, if you read this through, thank you so much, secondly, sorry if the grammar is wrong here and there, english is not my first language.

About half a year ago I [27M] had a crush on one of my coworkers [26F]. We are working on different departments, so I barely see her, few times a day, mostly from afar, but because I work at the IT department I helped her a few times remotely and we started texting. It lasted only a few days, nothing special, mostly small talk, but she seemed interested in me. Then she started ghosting me, I never even had a chance to ask her to grab a coffee with me at work. (I probably could have, but I wasn’t fast enough or idk.)

I really liked this girl so it hurt, but I acknowledged it that she’s not interested in me at all. We haven’t even texted nor spoken in person since.

In the past 2-3 months I noticed that she started avoiding me pretty openly. Just a few examples, my coworker and I are making coffee at the dining room, she and her friend arrive, her friend comes next to us to wait for the machine, she waits at one the tables in the other end of the room until we leave. Another example, I’m going home, it’s raining outside, when I leave the building saw her at the bus stop with plenty other people, the bus is like two minutes away, but when she notices me starts to walk home in the rain. Or for example this morning raining aswell, me and my coworker wait the bus at the bus stop because it is protected from it, she and her friend arrive, her friend stands next to us from the rain, she stops from us 5 meters away in the rain alone. I don’t understand this behavior, as if I’m carrying some desease. Even my coworkers started to notice it. I’m not that interested in her anymore, but these things kinda hurt me.

I’m curious what can be the reason behind this behavior? Any of you have any ideas? I thought about asking her, but she would probably give me some answers that nothing to do with it.