Crush on girlfriend - tell her or not

Hello everyone,

There are probably dozens of similar cases, but I'm still a bit desperate and need some advice.

I am male, have been studying for two years and have built up a good but purely friendly relationship with a fellow student during this time. We have done things outside of university from time to time, but our friendship is generally characterized by learning together, somewhere between platonic and good friends.
Especially at the beginning of the friendship, I had the feeling that she was more interested, but I wasn't interested in anything more than just studying and drinking a coffee from time to time. I found/find certain character traits rather repulsive.

This has changed in the last 3-4 months: I initially felt uncomfortable after meeting her and constantly felt the need to present myself positively to her by adapting certain character traits until I realized that I just liked her. This is just getting "worse" as I have to think about her more and more often, loss of appetite has also started recently, etc.

The problem now is that I feel like I have zero chance. My feeling is that she has no romantic interest (if anything, there was interest at the beginning), as I have kept the relationship quite "technical" so far (which now seems to be my downfall)

I'm now in a dilemma as to whether I should tell her with the risk that she won't be interested anymore. I also considered that communicating might also have a relaxing effect for me: if she rejects me (I think 90%) I'll keep my distance

On the other hand, I still have to work on a joint project with her for at least another 10 months, which could be unpleasant, or it could be difficult to keep my distance.

What are your thoughts on this?

Greetings krk

Would she be receptive to an e-mail? In other words, you can tell her about your feelings and if she doesn't reciprocate you can drop it and act like nothing happened. This gives her time to think about it, and if she is not interested the whole thing can be dropped without having a "confrontation."

Of course that would still leave you the pain of rejection but it would maintain the friendly relationship, especially since you have to work together for the next 10 months.