Love affair and tragedy.

It seems that writers’ are always seeking for spicy affairs and tragedy,especially forbidden relationship are always more inspiring, I guess. As examples, Gertrude, Hamlet’s mother, had a tragic final for her affair with her brother in law, Claudius, who also poisoned his own brother. Dante Alighieri, in The Divine Comedy, portrayed the Love of Francesca da Romini that was murdered by her husband Giovanni because she had fallen in love with his brother Paolo Malaestra. Is forbidden affair dangerous,incestuous or inspiring?