Affection, friendship, understanding, or wanting what's best for another person are not simplistic chemical reactions. They are also forms of "love" depending on how one defines it. My own philosophy (your mileage may vary) is that people change and relationships change with them, so these forms transition from one into another and that's the only way to keep a relationship going for decades. I was referring to cathexis specifically -- that is the most short-lived form of love. The feeling of one-ness makes it easier to treat another person as if they are one's own self. That's why the start of a new relationship so effortless compared to the effort of actually sustaining it. Unhealthy relationship expectations are based solely on the rose-colored glasses of a beautiful and precious chemical influence. It is all-encompassing of the springtime of the universe and everything in it from now unto eternity, and therefore simplistic. Healthy expectations, IMO, enjoy that rose-colored feeling but bear in mind the reality of change.