My family moved a lot too (military service). I pick up accents and talk like whoever I am talking to at the moment, automatically. We lived in California when I was little most of the time, went to Spain for a couple of years, Texas when I was in high school, etc. I can do the Southern drawl, or whichever accent fits. There was a time (when I was probably trying not to drawl) that someone told me my accent sounded a little British (maybe picked up from someone in Spain). Once I took a dialect test that I found online, and it said that I was 60% Southern (only lived in Texas for 5 years). I think that adapting to where you are is normal.