I am just like you. I keep my house warm in the summer and cool in the winter. I don't think extreme swings in inside and outside temperatures is healthy. I rarely get a cold, but I do get stopped up in rooms that are too warm. I am in a wheelchair and being ill is extra hard. I am wrapped in a cozy throw as I'm typing this. I agree a humidifier is a good idea as long as it is easy to clean so it won't be a source of mold.