I think it depends on the relationship.... I met my now BF in Sept and he moved in to my house in Feb, and we have been going strong ever since... actually our relationship blossomed even more since we live together. Just depends on the people and the relationship as a whole. We got to the point where he might as well just move in, since he was at my house 4-6 night a week... we always wanted to be around each other, we hated to leave one another. So we decided to make it official and he moved in - its been great.