I have one of my work colleagues who has become my friend.However we work in different countries .We used to share everything and anything mostly and chat for literally however long we were awake for. The problem started when people in the office started bad rumours and bad mouthing.I have shared couple of conversations with some of them taking them into confidence but that back fired as they spread that all over the ofrice. Now even though we are just ok  friends the closeness and the warmth isnt present. I have apologised many times but to no avail.She just said whatever I might do or think her behaviour towards me isnt going to change. I know behaviour changes every time but need some guidance on what I can do to change this reality. I have written a write up for her and she shared with our common friends that she felt sad for me. But again he behaviour is a bit weird , the other day we were chatting alright but she suddenly said. "I want to tell you something dont feel bad but dont use dear etc words when talking with me". She was fine with that al these days but not sure why now? I asked her the same and she said she dint want to answer.

I just want us to be back very good/close friends. Please help .
Thanks