When we were a family of three, we lived aboard for 3 years, full time, at Mears Marina on Back Creek (the ''back door'' to Annapolis). Comments about ''freezing to death'' reflect inadequate heating capability on a boat, not a general inability to be comfortable year-round in that climate. Just like liveaboards in the Northwest, a serious diesel-fired heating source is recommended (forget about AC space heaters, especially when the dock power goes out!) but a forced air system (Espar e.g.) will handle the weather just fine.
I''d recommend against the Back Creek marinas mentioned (Bert Jabins, Port Annapolis, Mears, etc.) if only because of the general setting these days. Mears was/is a great marina (with complimentary Yacht Club membership included) and walking distance to downtown Annapolis is as good as it gets when living aboard. But the creek is cheek to jowl with boats; living there would feel like camping on the freeway median, to me. You also buy into Annapolis/Eastport traffic, which is intense and relentless at its best.
Deale and other small communities further south on the Western Shore provide commuting access to the DC work settings, offer the ambiance of living aboard on the Bay as it can be, and provide pretty, back road drives into Annapolis on the weekends.
Jack