All depends on how you want to do it. I lived at the BOQ on base at first during API and it was great in many ways. Roll out of bed 20 minutes before class, crash at your room for lunch hour...etc. But having your own place means having your own place away from the base which I find a lot more satisfying, but then you get to commute every day. I've heard both good and bad things about on-base housing, if you can get it in the first place. Your only expense is cable, phone, electricity but again you are permanently on base and under the juristiction of housing management. I hear that can go both ways.
As for where to live later on, that may depend on where you go. In P-cola you have scores of apt's, rental houses, condo's, beach houses to choose from. In other boondock towns (where the DOD loves to build bases!!!) the on-base housing may be the nicest place you can find, or that the nearest apt's W/O giant roaches are an hour away. It all depends.
As for getting hitched, again, up to you. I'll say it's nice to come home to someone permanent who'll take your mind off the stress...by giving you different stress! JK, The single guy may have more free time to study (or for PS2)but he also has a lot more time to play with that long, thick, rope the Navy issues all SA's to hang themselves with.
Good luck!