In Chapter 5, appropriately titled "Katharine," the narrator hints that the English patient and Katherine's passionate relationship will come to an end, for Katharine is still married to Geoffrey and terrified of her affair being discovered. The English patient harbors this fear as well. As the two characters part, the English patient cannot help but ponder the tragedy of Katharine's youth, an observation Ondaatje illustrates through a simile: 

All that is alive is the knowledge of future desire and want. What he would say he cannot say to this woman whose openness is like a wound, whose youth is not mortal yet.

The simile “openness is like a wound” heightens the imagery of Katherine’s personality and her complex relationship with truth and lies. Her honesty and her youth have the ability to emotionally harm the English patient, given the impossibility of their relationship's continuance. Additionally, Katherine’s openness festers within herself: she is not wholly honest, as she cheats on Geoffrey with the English patient. However, her desire to love and be loved causes her to cross boundaries and in turn harm those she loves. The English patient feels infected in a sense by the love he has for Katherine: he feels he must claim her as a partner and lover—even going so far as to imply, later in the novel, that he had sex with her dead body after its discovery. Thus, the simile "like a wound” hints at the tragic, inevitable, and ultimately infected end to Katherine and the English patient's love story.