The media image of computer dating is that finding a mate is all about discovering how compatible two people are. The more interests they share, the better. We married folks know different. Successful living with someone else has more to do with tolerating incompatibilities. I'll go so far as to say that it is impossible for two people to live together without irritating each other in numerous ways.
On a boat, with only 200 square feet of living space, the problem is the same qualitatively, but the magnitude is intensified. Many couples are likely to say, "We could never do that." They're probably right. Finding three astronauts to fly a two year mission to Mars is going to be very difficult.
I observe that living in close quarters requires giving your mate extra generous room to be himself/herself. That does not mean suffering/stewing in private as you keep your mouth shut, because pent up emotions eventually erupt (especially in close quarters). It means being generous enough to be comfortable with your mate's idiosyncrasies without resentment.
Evidence suggests that Libby and I are pretty good at that. Individually, we are no less annoying than anyone else. But we get along really well; even in extremely close quarters.
Having said that, if you find an annoyance that is really persistent and will not go away, then you must bring it up. I've learned from Libby to express my annoyance is the gentlest possible words when necessary.