I believe sometimes dreaming about things or people in the past means we have an issue we're trying to deal with from that "period" of time. I lived in an apartment for 13 years back in the 1970's and early 1980's, when I was first in therapy with T. Then, when I started therapy with her again in 1996 (to 2005; I moved from the apartment in 1985 and terminated therapy with her the first time in 1987) I started dreaming about that apartment a couple times a month! I was probably dealing with issues I'd avoided/not dealt with when I was in therapy the first time and lived there. The dreams of that apartment ended around 2002 (after my stepmother died and other issues had been resolved in therapy).