What does Sex with Jim represent?

The occurrence of sex between Louisa and Jim symbolizes the tension between hope and despair. Louisa has sex with Jim after telling him the story of her pseudo-relationship with Jack. The sex itself could either be interpreted as Louisa having moved on from Jack or as Louisa desperately attempting to move on. It could also be interpreted as a mixture of the two motivations demonstrating the possibility of their intermingling.