Being lovestruck means having mental and physical symptoms associated with falling in love: 'love-struck. It means to be hit by love...you are hit in your heart by the emotion of love'.
Historically, being lovestruck has been viewed as a short-lived mental illness brought on by the intense changes associated with real deep, strong and close romantic love. Avicenna, a Persian polymath, viewed obsession as the principal symptom and cause of romantic love sickness. This diagnosis has been out of favor since the humoral model was abandoned, and since the advent of modern scientific psychiatry.
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