If a relationship dies, we conclude that we were merely infatuated. When the passionate love settles down into something less intense but more attached, that's when you start to notice a difference. LOVE Jacqui, for example, is usually pretty high strung. But when she fell in love, she felt peaceful and contented for the first time. To ask if it IS love indicates doubt.
Love is sure.
But relationships start in different ways. Infatuation, for example, is passion alone. Romantic love is passion paired with intimacy. Even with these definitions, recognizing The Big L is still a mystery to many. To ask if it IS love indicates doubt.