I may be naive but how can a person say that you are a friend then turn on you with such venom that they try to get you sacked from your job?
I think this person must be very sad and lonley. All I ever wanted was to be a friend oh well. I would just like to add that If you do like someone tell them. What ever the result at least you will never have to think "what if" and you may never have another chance.