Why do I keep having dream of me in my ex boyfriends house?

I keep having that im in his house..when I never went to his house in real life.we broke up 12 months ago.the last dream I had of it,i was in his house and he was snoring and sleeping in his room (he didnt kno I was there) and I was hiding in this other room so he wouldnt find me.but I was trying to get out then I checked he wasnt sleeping anymore. So Then I found my way out of his house before he caught me. And ran up these stairs..What does this mean???