Yay married characters, up with this sort of thing. Aldrith and Mitara need more properly married Amarrians to have dinner parties and family gossip sessions with. I think.
But yes, I cannot stress enough the importance of keeping in-touch OOC through an instant messenger program or something similar. Both Mitara and I have quit the game for periods and never once has the question of it affecting the in-character marriage ever come up. When I quit, for example, the IC explanation was that Aldrith had simply retired from capsuleering to stay close to his family. IC this absence actually strengthened the marriage, and Mitara and I spoke at least once a week talking about what each other was up to, and to maintain a friendship beyond our characters. Aldrith's reason for returning to capsuleering also affected Mitara as a character, all of which was discussed prior, making for smooth transitions and ensuring everyone was on the same page. Ald and Mit's 2nd anniversary just passed and even though neither of us were in-game to RP anything for it, we both agreed OOC they did something terribly romantic and it was great!
Now start popping out kids so we can arrange marriages between each other's houses and then get into feudal family political intrigue battles Game of Thrones style.