2 Samuel 13:2
And Amnon was so vexed, that he fell sick for his sister Tamar; for she was a virgin; and Amnon thought it hard for him to do any thing to her.
Cross-reference
1 Kings 21:4
Parallel
In 1 Kings 21:4, Ahab becomes sullen and refuses food over Naboth's vineyard — a parallel to Amnon's distressed illness from frustrated desire.
Song of Songs 2:5
Contrast
In Song of Solomon 2:5, the lover is sick with love in a positive, mutual context, contrasting with Amnon's destructive lust here.
Song of Songs 5:8
Contrast
In Song of Solomon 5:8, lovesickness is romantic and mutual, contrasting with Amnon's obsessive, sinful lust that makes him ill.