Hey there buddy,
Unless you've had dreams in which you've predicted events to happen, your going to be all right! You and her, anyways.
Every part of a dream is you. The unconscious mind takes elements from our everyday life and puts them in a way that would seem puzzling but after careful thought, you'll begin to understand.
Without much detail of the dream, I can only give a small sketch as to what it means. Death is usually a meaning that something has changed dramatically. In your case, your best friend whom your implying is female. This female characteristic could signify your own feminism and that its decaying away.
(Metaphorically towards Friendship): Has she changed in someway that your feeling is distancing you both? Is there something you remember about her(Picture on Lamp Post) that illuminated your day now is just a fading memory?
(Metaphorically towards yourself): Have you changed in a way that is not who you are? Have you done something that is not of your own nature? Is there something in your past (Picture on Lamp Post) that happened recently you wish you could have back?
Dream again and see if any more images show up that result in some awkward change.