The Hebrew word translated “heart” in these verses means inner part, soul, heart, mind. It’s the same word used in Isaiah 61:1 that foretold that a facet of Jesus’ mission would to be to set people free from the side effects of growing up in a fallen and dysfunctional world … He sent Me to heal the broken hearted (brokenhearted is 2 words in Hebrew).
Two extremes are presented in Proverbs 15:13 and 15: the glad heart but also a sorrowful or aching heart. There are also many intermediary conditions of how we are doing on the inside. Jeremiah 17:9-10 in the Message says: