She wants her relationship with her bf to work out, he may or may not be controlling she wont be able to see that. All as she knows is she wants a future with him. One of you had to go.
Oh my! My heart goes out to you and I wish I can make your ease your pain. There were two ppl in this friendship and she told you her experience of it. It was her truth and why she could not continue the relationship. You need to respect that. She realised you had feelings for her that she did not share so this made her uncomfortable. Dude as painful as it is its better for you to move on and make peace with the fact that you have feelings for her and will never be able to be just friends. Good luck.
You have to let her go, move on. I'd argue she has developed feelings for you, and can't handle this as she has a bf