When the Wife of Bath first uses the word love, she really means sex. Yet, by the end of her Prologue, when she tells us that Jankyn was the husband she loved best, we get the feeling that love actually means love to the Wife. For her, love is inherently linked to money; she tells us that love too freely given is not valuable because it's "cheep," in essence inserting it into a free market economy of supply and demand. As she does with sex, the Wife withholds love in order to increase the value of her love on the open market. Her success at this means that by the time she meets Jankyn, the Wife is wealthy woman who has bartered love and sex for money on numerous occasions. Consequently, she is able to marry a penniless scholar like Jankyn. Arguably, the money the Wife has gained by selling her love has enabled her to finally marry for love. This last marriage brings the Wife's economics of love full-circle: the Wife traded love for money in order to forego money for love.
The Wife of Bath's leveraging of her love (or the appearance of her love) for money enables her to actually find love at the end of her life.