It's been a long time ago but I'm curious to know why this female friend stop talking

[Locust]

I met this lady who is Russian back in 2010 in my math class. She was the first to approach me and so that is how we met. I remember one moment me and her was riding the same train home and she was talking, but she was taking her finger twirling her hair and looking at me a lot. But I never put much thought in it. She knows I’m a science major and she text me one day saying she joined a physics club and I was pretty surprised because she was a business/economics major. However, I never joined the club. Then one day I was on campus with my friend and she came and talked me about field trip with the physics club to a lab and I was saying I’m not sure if I can come that day. She was literary asked me 3 times straight, but I notice she was clutching her hands a lot like she was a bit nervous.

 

Then back in 2012 I had my birthday coming up soon and I was going to invite her to a party. But I end up going to a local gathering and met a lady there. I went on a date with that woman and the Russian woman text me later that day. Since I was on Facebook I send her a message there and told her I was on a date yesterday evening. From there I never heard from her again. It’s like she went poof!! I text her days later and she never replied. Weeks went by then months and I just said oh well she doesn’t want to talk to me anymore. I deleted her number and her off of Facebook since I felt I was being ignored. She was cool friend but to this day I still wonder what happen. Maybe you guys have some ideas what went wrong in our friendship.