I don't travel at all. DHs travel varies. Sometimes it's slow and he doesn't travel at all, sometimes he is gone a ton. He was gone for 2.5 months in fall 2011. Lately it's averaging about 1 per month but I think he said it's about to get busy.
H travels anywhere from one to four or five times a month, sometimes just one overnight and sometimes up to three nights. I don't think he's ever been away longer than that.
For me, maybe a week every 3 months or so. Give or take. DH, once or twice a year, but the trips are only because of emergencies, so the length of time can be open ended.