Guilt is heavy. Ever get a sinking feeling in your abdomen when you feel like you didn't live up to your own standards? Or experience a sensation of something weighing on the conscience, like you were carrying something heavy? The weight of guilt has even been shown to make physically demanding tasks seem more difficult. [1] And letting go of it can be tough.
In Chinese Medicine, the mind, emotions, and the body are intertwined, and we can use the points on the body to help resolve emotional issues. Some of the most powerful points for dealing with guilt are found along the Belt Vessel, the only major acupuncture channel that runs horizontally. As its name implies, the Belt Vessel encircles the waist, but drops lower in front as though weighted down. This channel is like a basement: a place to stash things we haven't quite figured out what to do with, or that we're not entirely proud of. We don't go there very often, and it tends to get stagnant and damp. ("Dampness" is the Chinese Medicine term for energy that's turbid, heavy, cumulative, and difficult to get rid of -- yucky stuff.)
To lighten up that damp basement and clean out the stuck emotional energy from the Belt Vessel, first, conjure up what you want to let go of and extend a feeling of forgiveness towards yourself. Then, bring your fingertips and thumb together, and with firm pressure, massage the following points:
Gall Bladder 41: on the foot, just outside the tendon that leads to the little toe, on the right side for women, on the left for men. This point opens the Belt Vessel. 
Liver 13: on the side of your torso, Dai Mai Point at the tip of the 11th rib
Gall Bladder 26: just below Liver 13, at the level of the belly button
Gall Bladder 27 or 28: On the low belly, just inside the hip bones
To enhance the treatment, apply a drop of essential oil to these points. Neroli, cardamom, sandalwood, or bergamot help the body resolve dampness and guilt while fostering a sense of peace. Since guilt tends to linger, you'll want to work with these points for a few days in a row, then take a break. Repeat that cycle until you feel a sense of lightness and liberation.
[1] Day MV, Bobocel DR (2013) The Weight of a Guilty Conscience: Subjective Body Weight as an Embodiment of Guilt. PLoS ONE 8(7): e69546. doi:10.1371/journal.pone.0069546