Frustrating Situation With Uncertainty?

Why is it that girls push and pull than get upset with the guy for not understanding but in reality he’s probably not the problem. I’m in a situation where I used to work with a girl for about 2 years and we used to work together as well and texted each other a lot went on a few dates and she always stared at me with admiration everyday we worked together. I left that job because of her and 4 months later when I see her she all of a sudden interacts with me she has rejected me multiple times but keeps showing up in my life. I don’t know what to do I’m just done I have sent her multiple messages but she hasn’t answered but when she sees me in person she bothers with me.
Frustrating Situation With Uncertainty?
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