It's wrong to give other people herpes knowingly.
Ian got herpes from unprotected sex and feels very angry about it.
Ian wants to take action on his anger.
Ian finds some treatments for herpes and spends his anger trying to stamp the disease out.
Ian sleeps with various people without informing them of his STD, so he won't suffer alone.
Ian goes into remission and doesn't infect other people.
Other people get herpes and suffer from the disease like Ian does.