I dunno about common today, I hear plenty of horror stories about graduate research and relationships with advisors.

The main point is that Einstein did his work in a vacuum, and yet he didn't. He was married to a fellow physicist, who understood some of his work. Just imagine that pillow talk.

If you're going to create a new, and successful, form of mechanics, it's probably best to be a little bit isolated, don't you think? The idea alone is isolating. Still, he wasn't "just" a patent clerk. He was credentialed to teach graduate physics courses at university, right? He just didn't have a job.