Synonyms for Heartsick (same or very similar meaning)
WordNet sense 1 (full of sorrow):
brokenhearted, heartbroken
WordNet sense 2 (experiencing or marked by or expressing sorrow especially that associated with irreparable loss):
sorrowful
WordNet sense 3 (without or almost without hope):
despondent
WordNet sense 4 (without hope because there seems to be no possibility of comfort or success):
hopeless
From the ODE community, based on WordNet
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