I only shower every 2-3 days. My skin also gets itchy and I just don't like dealing with my hair. If I am going out in the morning, I shower the night before. If I'm going out at night, I shower early and then let my hair dry. I just touch it up with a blow dryer.
I sniff myself a lot and I don't smell bad.
There is a thread up in the "bipolar success stories" on showering. I think it is a very common problem.