Part of every misery is, so to speak, the misery's shadow or reflection: the fact that you don't merely suffer but have to keep on thinking about the fact that you suffer. I not only live each endless day in grief, but live each day thinking about living each day in grief.
Much of the modern resistance to chastity comes from men's belief that they own their bodies -- those vast and perilous estates, pulsating with the energy that made the worlds, in which they find themselves without their consent and from which they are ejected at the pleasure of Another!
If, as I can't help suspecting, the dead also feel the pains of separation (and this may be one of their purgatorial sufferings), then for both lovers, and for all pairs of lovers without exception, bereavement is a universal and integral part of our experience of love.
You ask whether I have ever been in love: fool as I am, I am not such a fool as that. But if one is only to talk from first-hand experience, conversation would be a very poor business. But though I have no personal experience of the things they call love, I have what is better -- the experience of Sappho, of Euripides, of Catallus, of Shakespeare, of Spenser, of Austen, of Bronte, of anyone else I have read.