I may be projecting here, but I fear the dissatisfaction people have with finding suitable partners and the social pressure to be in a relationship has caused the adoption of fantasy relationships. There's never been a time when we've grown up more used to being ourselves, yet we seek relationships that require compromise. We'd give up relationships altogether if people didn't keep asking us about them and encouraging us to get involved with someone. Some of us, of course, have always felt alien, so perhaps a fantasy alien spouse makes sense.
On the other hand, 'That guy has a girl in every spaceport.'