Synonyms for Distressing (same or very similar meaning)
WordNet sense 1 (causing distress or worry or anxiety):
distressful, disturbing, worrisome, perturbing, troubling, worrying
WordNet sense 2 (marked by great psychological weight; weighted down especially with sadness or troubles or weariness):
heavy
WordNet sense 3 (bad; unfortunate):
deplorable, lamentable, pitiful, sad, sorry
WordNet sense 4 (having undesirable or negative qualities):
bad
From the ODE community, based on WordNet
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