I don't think you should infer from this thread that travel-heavy jobs are unequivocally miserable, but simply that they're not for everyone. If you hate children you shouldn't become a kindergarten teacher, and if you don't like being home you shouldn't spend your days cooped up in a home office. While being away a lot has its disadvantages, I don't think I could be happy in a career that didn't involve frequent travel.

As for what we do for a living, there are other threads where this is discussed extensively; search titles for "jobs travel" or something like that.