Said she might fall in love with me

Hi, I'm in need of some advice and sometimes its best from strangers. I have been working on a project with a woman for 8 months now, we are artists, we have become close friends and there gas always been a sexual tension. We are both single but she has been single for along time because she's been hurt badly in the past. Anyhow, after getting to know her I fell in love with her and I felt hot/cold messages from her. We spoke about my feelings in January and she said she only wanted to be friends but also said she might fall in love with me one day. We continued to work togethet on the project but her words of possible love inserted a hook into me and I recently had to cut that string as it was torture and hurtinf hoping this girl might fall in love with me as she said. I changed things in my life hoping that would do it but it became too much being on that string. Since I cut the string she has become depressed and heartbroken and I'm very concerned for her as I know she has many problems. I love as a friend but it just became too hard to 'just be friends' with her. I've never had a woman say she might fall in love with me, it's a strange thing to say to a guy she knows is in love with her. I look forward to your advice :)

Thank you susiedqqq, much of what you wrote resonated with me :)