'Bitter' in the Bible

Then David gave way to bitter grief, and so did all the men who were with him:

Then Abner called to Joab and said, “Shall the sword devour forever? Do you not know that it will be bitter in the end? How long will you refrain from telling the people to turn back from following their brothers?”

And Hushai saith, 'Thou hast known thy father and his men, that they are heroes, and they are bitter in soul as a bereaved bear in a field, and thy father is a man of war, and doth not lodge with the people;

And the salvation of that day was changed to sorrow for all the people: for it was said to the people, The king is in bitter grief for his son.