Long term relationship is bad for women's sex drive
Here's one good reason why you ladies should not stick to a guy for too long if you value your sex drive. From BBC:
The researchers from Hamburg-Eppendorf University Hospital interviewed 530 men and women about their relationships.
They found 60% of 30-year-old women wanted sex "often" at the beginning of a relationship, but within four years of the relationship this figure fell to under 50%, and after 20 years it dropped to about 20%.
In contrast, they found the proportion of men wanting regular sex remained at between 60-80%, regardless of how long they had been in a relationship.