sorrowful
afflictive
agonizing
calamitous
consuming
desolating
dire
distressing
excruciating
grievous
harrowing
heartrending
heartsickening
heartwounding
lamentable
racking
regrettable
rending
tormenting
torturous
unfortunate
break someone's heart
heartbreaker
awesome
breathtaking
daunt
frighten
frustrate
gruesome
horrific
humiliate
macabre
piteous
poignant
saddest
scary
tragic
unbearable
unforgettable
woeful