[jojocomok]

Guilt as i understand it is an inner conflict between something we have thought, said or done and our ideals (the super ego).

There are different ways to deal with it:

1- To stop thinking about the past and to move on (most Buddhists follow this way i believe)

2- Not suppressing the experience that caused you to feel guilty but to keep on memorizing it and analyze the situation and to see that its not as big as you think it is (to see the biases in your mind), and to try to forgive yourself (i think most modern psychologists follow the second method)

Finally, all negative mental states (including guilt) are caused by the delusion of the self (the ego). So if you can stop taking everything personal and remind yourself that your emotions, mind and body are not you, that would solve not only guilt, but all negative emotions that you might experience in the future.

Regards,
Bundokji