Me [26M] and my coworker [24F] - she turned me down, but has issues with me dating other women. now it appears she only wants my attention..

I developed romantic feelings for a coworker that I am very close with. I asked her out, and was turned down. We both decided that we should be friends. I have since moved on from her, but she has made my life very difficult at work and strained our friendship. Some examples are:

1. Out of the blue, she would send me random pictures of the men she is about hook-up with or snipbits of conversations of men hitting her. I tell her 'Did you send this to the wrong person?', or 'Sorry I am confused.'. She would not respond..

2. Colleagues and I went out to a bar to celebrate the company closing a record sale. My colleagues start taking shots to commend me for getting a date to a concert. Everyone is shouting and making explicit comments, which evolved to a chant of "[26M] got a date tomorrow!" Then I (sober as a rock) see [24F] giving the death stare at the person who started the chant. Thought I was seeing things, I asked the waitress if she saw what I saw...She said, "good luck with her." Waitress then pointed at [24F].

3. As part of a company celebratory event, the Company paid for everyone's flights to a nice resort for skiing & snowboarding. I had a sales meeting the morning of the departing flight, and I booked a later flight to the event. She scheduled a morning flight with the everybody else. She asked me if I wanted her to fly out with me. I said 'no, you should go with everyone else and enjoy the snow." Guess what? She changed her flight to be on the same flight as me...

4. Folks...it gets better!!: During the company trip, I decided to determine if she is interested in me (again). Nope!! The entire 4 day event, she avoided me like the plague. Everyone went out on a night on the town, and she wouldn't talk to me at all. Even in a casual setting, she would avoid me when we are in the same group... But then once she leaves the social setting, she would text me and try to carry a conversation via SMS.

TLDR: I am now happily back in the dating scene, and no longer have any romantic interests towards my colleague. But I consider my female colleague someone I trust and still consider her my good friend. But I cannot make of her actions. Why is she acting this way towards me? What should I do about her actions?