OBDURATE

unyielding

hardhearted

intractable

stubbornly persistent in wrongdoing
SYN - cursed, obstinate, unrepentant

showing unfeeling resistance to tender feelings
SYN - flint, flinty, granitic, stany
ANT - regenerate
"The child's misery would move even the most obdurate heart."

"The years of hardships and tough-times made him obdurate to her appeals for his heart."

"The president prided himself on being obdurate about the Iraq War."

"He had gotten this far in the ruthless business world by by obdurate in such circumstances, but he knew this was a defining moment in his life were he could really do something that mattered."