Hi Matt, unfortunately Apple made a lot of changes in how multi-monitor stuff works in Mavericks, and it's causing a lot of various different problems. 
 
But from what I've heard it should be possible for you to change a OS setting to make things behave like they used to before Mavericks and that may help to avoid this from happening. 
 
The setting is under System Preferences > Mission Control - uncheck "Displays have separate Spaces" there. 
 
You will then need to reboot your system in order for this change to take effect. 
 
Does it behave any better after that? 
 
      - Michael 
 |