Quite a lot of our contemporary culture is actually shot through with a resentment of limits and the passage of time anger at what we can't do fear or even disgust at growing old.
Anger will never disappear so long as thoughts of resentment are cherished in the mind. Anger will disappear just as soon as thoughts of resentment are forgotten.
Guilt is anger directed at ourselves - at what we did or did not do. Resentment is anger directed at others - at what they did or did not do.
Holding on to anger resentment and hurt only gives you tense muscles a headache and a sore jaw from clenching your teeth. Forgiveness gives you back the laughter and the lightness in your life.