What THS said can be true but even this dream situation may not be as smooth as it looks.
First the posting dates may depend on other people's moves which can be dictated by their career paths, courses, dets etc. You might find that you are both posted but not at the same time. This gives you a quartering conundrum. Does first mover set up in remote quarter and last mover go in to the mess or vica versa?
In a standard tour you could possibly drift 6 months apart at either end giving you only 18 months colocated.
If you are groundcrew you posting might, to all intents and purposes be permanent. Ditto some aircrew. Whereas other jobs, non-aircrew officers, would expect moves as soon as 18 months for a first tour and 2-yearly or so after that. 2 1/2 years or more and you are letting grass grow over your feet.
As you mount the greasey pole you could again expect postings as the number of billets at the higher ranks become fewer. You will get used to it.