Feeling guilty may feel like being in a prison with no key - however the fact you are remorseful is the first step to forgiving yourself, dealing with the guilt, and behaving differently next time
Guilt is an uncomfortable feeling coming from real or perceived wrongs we feel responsible for, whether or not malice was intended. However, it can be dealt with such that we are less likely to have to confront this difficult emotion with regard to the same sort of situation in the future. In this way guilt can actually be managed constructively.
Firstly, to experience guilt, tell yourself the fact you feel this way is a strong indicator you are not Ďa bad personí although you may have performed an action you feel uncomfortable about, or that was, in your eyes, wrong.
Also, keep in mind a lot of actions we later regret are spur of the moment, not at all planned. For example, we donít often plan to lose our temper. Actions done in the spur of the moment in anger were not planned, and now your realise that though the behaviour was not great, you yourself are not 'bad', you are now in a position to deal with the guilt.
I am not talking about guilt which should not even be there, when for example you feel you should have done something that you felt obliged to, though in reality you actually werenít expected to. I am referring to those actions we all do from time to time where in retrospect we realise we are in the wrong.
Second, know you canít go back in time. However, both to be able to move on and to make the best attempt you can to mend fences with the other person, sincerely apologise from the heart to the other person. This can also be cathartic.
Third, ask yourself, what would you have differently if you could replay the situation again? Mentally rehearse it, so that if a similar context arises that cause those emotions to surge to the surface again, you can visualise and experience the actual feelings of a different way of reacting. For example if you regret becoming angry and raising your voice, picture yourself breathing calmly instead. Feel yourself be calm into this projected hypothetical situation, as though it were the present, so you can make real to yourself your ability to react differently.
During your next interaction of a similar nature, or which provoke similar feelings (such as anger, as this is a common emotion to regret), behave as you imagined you would. You may still have feelings simmering underneath the surface. However, grow in confidence that at least you calmly handled it this time do (further) damage to the relationship. The fact that you apologised and the relationship meant enough for you to rue and to want to behave differently may lead to it becoming stronger in the future.
Guilt feels terrible, but the fact we have remorse is an indication youíre not a bad person. Learn from the situation which caused you to feel regret, and after you have apologised, move on. And then focus in the future how you have grown and feel pleased with your improved way of handling your emotions and that your relationship is intact.