it already has.
It's called getting engaged. It starts with just a few females infected with the "marriage" pathogen who lure their males close enough to become infected. This results in erratic behaviour in both parties usually characterized by a euporic state, impulsive actions, increased intimacy, and rapid depleting of financial reserves often in an attempt to gratify and to add showy adornments to the female and resulting in various public displays. Both the males and females generally become more vocal, particularly with each other. Both individuals typically will virtually abandon their former social groups. This results in other females in the immediate social group trying to reconcile with and emulate the infected female by also becoming infected and luring their males (or free-ranging males they are able to attract) into the same destructive cycle. Males are typically lured in by the promise of promiscuity that is usually short-lived or never materializes at all. Some resistant individuals of both sexes may fight off the infection and return to their former pre-infected condition but normally this results in a severing of the social relationship with the forrmer partner and/or abandonment. Once the pathogen runs it's course those unable to fight off the infection enter the "marriage" state. For most males this is considered analogous to death. Females may persist in this state for some years but eventually they too succumb psychologically.