Synonyms for Lonely (same or very similar meaning)
WordNet sense 1 (lacking companions or companionship):
alone, lone, solitary
WordNet sense 2 (without accompaniment or companions):
unaccompanied
WordNet sense 3 (not seeking or given to association; being or living without companions):
unsocial
WordNet sense 4 (marked by dejection from being alone):
lonesome
WordNet sense 5 (affected or marked by low spirits):
dejected
WordNet sense 6 (remote or secluded):
unfrequented
WordNet sense 7 (capable of being reached only with great difficulty or not at all):
inaccessible, unaccessible
From the ODE community, based on WordNet
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