Idiom of the day :- Eat one’s heart out

Usage, examples and definition of the Idiom :-

‘Life can be terrible at times,’ Mike sighed, ‘and this is one of those times. I’m in love with Mandy and Mandy doesn’t care for me. Oh, Mandy, you have me eating my heart out !’ Poor Mike. If he doesn’t look underfed it’s because to eat one’s heart out is to feel miserable wishing for something — or someone — one can’t have.