As was said earler: dehumidification, and/or venting.
Keeping the air in the trailer moving (fans) will help because the moving air keeps the exterior surfaces warmer, so less reason to form condensation.
Get a humidity gage. Have some idea of just how big your problem really is. They are cheap and easily found at Target, Walmart, lumber yards, etc.
BTW, it comes up every year: some people try to heat with propane heaters inside a trailer. The result will be lots of moisture. It isn't a good idea, just like 'ventless' fireplaces aren't a very good idea for more than occasional use. Use the furnace (combustion fumes are vented outside with the created moisture) or electric heaters.