heartbreaking

heartbreaking /ˈhɑɚtˌbreɪkɪŋ/ adjective
heartbreaking
/ˈhɑɚtˌbreɪkɪŋ/
adjective
Britannica Dictionary definition of HEARTBREAKING
[more heartbreaking; most heartbreaking]
: causing great sadness, disappointment, etc.

— heartbreakingly

adverb [more heartbreakingly; most heartbreakingly]