““We were so busy thinking about protecting ourselves that we didn't think about the happiness of anyone else who might become involved with us. As a result, our rules focused on our own relationship. We thought that if we preserved the relationship between the two of us, the "core relationship," we were doing the right thing. We never considered that rules that worked for us might not work for the other people we would come to love, and we certainly never looked at our relationship from their perspective.””