Do you have a low point like the front slider window cracked and an upper vent cracked? You need to have a means to let the air flow naturally to whisp away the moisture. I usually crack the slider window about 1/4" and a roof vent about 1/4-1/2 turn. When I cook, I open the roof vent more and the window behind the stove about 1/2-1". When you take a shower, make sure to open the nearest vent about a turn and leave it open for at least 15 minutes after the shower while it's still drying.
If you are having condensation on the windows, you need a bit more ventilation.
Some folks have built or use a heat exchange air flow system with a small fan. This way you exchange the air without losing hardly any heat.
You have the same problem in the house, but there is such a larger volume of air and enough natural leaks that you don't notice it.