contriteness, contrition, guilt, penitence, regret, remorse, remorsefulness, repentance, rue, shame

compunction, misgiving, prick, qualm, scrupleblame, culpability, faultliability, rap, responsibilitychagrin, embarrassmentanguish, distress, grief, ruth, sadness, sorrowbloodguilt, bloodguiltinessapology, excuses, hand-wringing, mea culpa