"I smiled at him, as Doyle squeezed my hand and I squeezed back. "Some people are addicted to falling in love, Doctor. Some people love that rush of new emotions, and when that first rush of new love is spent, they move on to the next, thinking the love wasn't real. What I felt in her, and potentially in you, is the love of years. Love that knows that that first rush of freshness isn't the real thing. It's the tip of the iceberg."