I’m glad it raises all these questions in just 167 words.
In my own mind, he had planned to kill her and then take off for Zijua. In the end he decides not to kill her, but leaves the gun as a message and heads off to a new life. I can see her taking up with the other guy and forgetting him — except maybe for the bothersome rogue moment now and again.
The “story” came to me as I walked across my bedroom and saw my shadow from a lamp behind me diminish as I approached the wall. My own TWK prompt.