I've only had one dream that I would consider lucid, but the only control I had over it was the ability to end it, which I did abruptly. (Scary dream)

I think that you are the only person that can truly interpret your own dreams. Because the objects and events that take place in our dreams are symbols created by our subconscious. Even though you can seek council from others to help in dream interpretation (based on the collective meaning these symbols represent) you are the only one that can understand what your dreams are trying to relay to you.

Interesting that you would have a conversation with yourself in your dream and even more interesting is that you saw an actual event in your life take place while you were dreaming. I think that's fairly rare, mostly because your brain uses symbols to represent what's happening in your life. Whatever you said to your friend must have really been eating at you.