Marina Adshade weighs the economic benefits of having a significant other:
All the data I have seen suggests that the men who have sex the least frequently, after men who have no sex at all, are those who report having more than one sexual partner in the previous three months. The men who have sex the most frequently, for example more than 20 times a month, are almost exclusively men who have only one sexual partner. So even though it may appear to cost less to head out to the clubs on the weekend than it does to wine and dine a girlfriend, given that the outcome of that outing is uncertain it is probably still the most expensive option.
The Dish 