In the Dark Series by Christine Feehan, Lifemate is the term used to describe spouses of the Carpathians (race). However, the bond between lifemates is much stronger and different than that of humans. A male loses his ability to feel emotions after reaching the age of 200. Those emotions can only be returned to him when he finds his lifemate, the other half of his soul. Lifemates must touch minds and share their bodies frequently. If they do not do so, one will begin to believe that the other is dead and might attempt suicide. When a male loses his lifemate, if he doesn’t “greet the dawn” (i.e. commit suicide), he will turn vampire by killing a human while feeding to get the ultimate high.