I have fond memories of sharing an apartment with a roommate and a house with 4 other roommates. Fun times!
During my final years of undergrad education, I rented a room in the basement of a house in a Midwestern college town. There were three other rooms in the basement, each rented to a male college student. We all shared a single tiny bathroom (no tub). All I remember is how disgusting the bathroom would get by the end of the week. Fun times? Uh, no.
I wonder now how I could have possibly lived like that. I suspect that the answer is that I was (1) young, and thus extremely flexible, and (2) delighted to be out of the college dorm and living "on my own". Now I'm living alone in a house with three bathrooms, and that seems about right. Call me spoiled.