So here goes. Good luck...
1) Fully accept that you will never forgive yourself
It is not your place to forgive you. By all means, be open to forgiveness from those you have hurt. It may help (though don't depend on it). But forgiving yourself for something you did to someone else... your mind will simply not allow it! You can't fool your way out of this by splitting yourself into two people ("I" and "myself"). In fact you risk all manner of mental health problems if this split becomes too sophisticated.
2) Remorse is selfish
Remorse is a useful tool, given to us courtesy of evolution, for ensuring you don't do what you did again. But be under no illusions - like all evolutionary tools, remorse is primarily there to protect and serve YOU. It ensures that you can function co-operatively within the social environment and therefore secure your share of resources and, ultimately, improve your chances of survival.
Obviously that's not so much of an issue in 21st century civilisation. But because of how remorse is hard wired into the human brain, it can still fuel your desire to help others, which will in turn make you feel more positive.
3) Lose the story, meet the feeling
Whenever you feel a pang of guilt, do not get entangled in the story that accompanies it. Put your attention on the place in your body that you feel the "pain". Focus your attention on the raw feeling, without judgement. You'll find it's just energy, and actually very similar to the raw feelings you associate with things like excitement and joy. When you take away the mind-made story, the feeling loses its painfulness. Instead you notice things like "faster heart beat" or "shortness of breath", maybe "butterflies in the stomach". Sound familiar?
All this time it was your mind making what are every day feelings a source of suffering. Lose the story and there is no suffering.
4) You are not your thoughts!
Yes, you did what you did, and the story, judgement and suffering develops from your memory of that. Nobody can deny the past happened, but it does not exist right now, in this moment, any more than in the form of a thought. Physically speaking, the past is a corpse that you keep alive through memory, thought.
What is a thought? Ask yourself what power thoughts have if you were to watch them pass like clouds. What control do you really have over what/when/how thoughts arise? Now ask yourself who is aware of those thoughts? Who is observing them?
That is closer to who you are.
The point is that to identify with thought is to enslave yourself to your impulsive mind and believe that you ARE those thoughts. This is the illusion many of us live under, obliviously, for our entire lives. It has been called by some the "inauthentic existence", because it is like veiling reality with the screen of mind.
5) If you are not your thoughts, you are also not your past
You DID your past. You are NOT your past. Understanding the difference between these two statements is crucial if you are to free yourself from the impulses of mind. Be patient with it, as it may take some time. Just because you've been brought up to take responsibility for your past (whether rightly or wrongly), doesn't mean you should extend that to believe that your past is who you are. How can it be? It is just a thought (as we established). You only exist in the present moment, therefore you can only be who you are, not who you were.
It's so simple, yet the mind can't help but complicate/distort it.
6) Accept that other people can't be certain you are remorseful
If anyone judges you because of what you did in the past, it is because they assume you still may be that person. The only people for whom this is perhaps true are the remorseless. Only you know if you are truly remorseful. But other people will only know that through the passage of time.
For all they know, you could have it in you to do it again. Show understanding for this point of view, but do what you can to show the world who you are today, now, in this moment. Think of when you talk to someone for the first time - you always judge them presently. You never think "I want to find out this guy's past before I'm nice to him". Nobody thinks like that, because the natural state is the only state that truly exists - the present moment.
It is only when our past is revealed that the judgement shifts to the non-existent. They now judge you on what you did, rather than who you are, for the simple reason that they do not know if you are still that person in disguise.
So if you want people to judge you based on who you are, do not reveal your past and don't feel guilty or dishonest about not doing so - if you are truly remorseful and are certain you will never do what you did again (remember, only you can know this!), then the present you is the only person worth judging.
7) Let go of pride and shame goes with it
Part of why you feel guilty for your misdeeds is that you betrayed your principles in some way. You damaged your pride, in other words, because you can no longer get on that moral high horse without a sense of hypocrisy.
We all know that feeling of putting others down to make us feel better about ourselves - that's pride in its ugliest element and it's nothing more than unashamed ego inflation. It has little practical use in the real world.
If you can let go of pride, then its opposite, shame, will also dissolve, because how can you feel shame if you had no pride to hurt in the first place?
Letting go of pride means you no longer take credit for things that you really shouldn't take credit for in the first place. Genetics and environmental conditioning (whether conscious or unconscious) made you the person you are. You can claim you worked hard, chose to do good etc. but these are all the result of a mind (and body) that is capable of producing these traits.
Do you take credit for not having the mind of a psychopath? No. So why feel ashamed for having the mind you do have?
8) Allow yourself to hit rock bottom
There is a cruel "reward" for those who feel true remorse - moments of despair, depression, even suicidal thoughts. As long as you are aware that these too are just thoughts, mind games, you will get through it just fine. Feeling bad is just your mind going through the motions of its conditioning. Let yourself feel #######5. Let the remorse burn deep inside you - the deeper the better, because the sooner you sweat this fever out of your system, the sooner you can get back up and look at the world from a fresh perspective.
You'll find that the typical pattern is two steps forward and one back. For example, I am currently going through a dark period. But it's not as dark as my first dark period was. I know there is light coming and I just have to give my mind the space to do its crazy thing.
By not resisting these dark periods (i.e. through drugs, escapism, denial etc.) they won't be as prolonged or frequent. By trying to repress thoughts and feelings, you risk pushing them into your unconscious and that is when things can get very nasty.
Always give your mind the space to do its thing, even if it makes you feel bad. Observe it, like passing clouds, do NOT identify with it.
9) The universe has no morals, it merely hosts actions and consequences
Although you can know who you are, you are in no position to know what will ultimately come from your bad deeds as equally as you aren't for your good.
That's not to say you should abandon your moral integrity (another evolutionary tool we can all use to our benefit). But have some perspective as far as the long term consequences of your remorse. If you are able to unleash the full potential of your remorse, be reassured that you will probably end up helping far more people than you hurt over this lifetime. But you have to use your remorse productively rather than dwell on it.
Remember, remorse is fuel. You need to burn it, turn it into energy. It's not supposed to be swilled around the mind - it's supposed to leave the body.
Take this scenario for some perspective...
A person murders 4 people. Let's say that person's remorse caused them to commit to charity work that ended up saving 100 lives over their lifetime.
Let's say that their work influenced the good deeds of others. Additional lives were saved/enriched as a result.
Was it right for that person to murder those 4 people? No, of course not (that's a subjective judgement).
Would they have saved those 100 lives if it weren't for the remorse of murdering those 4 people? Probably not (that's an objective statement).
When judging regrettable events, don't just look at the immediate consequences. If our aim is to minimise negative consequences, then make it so - go out and make good from bad. Make it so that if the bad had never happened, all this good would not either. Create that moral dilemma and challenge people with it! They will have to concede (but will most likely use the irrational part of their mind to pretend that good from bad is still... bad).
Remember that progress demands sacrifice. Continue to regret your past misdeeds if you must, but know at any moment you have the power to turn that regret into something amazing.
Or maybe you're afraid that one day, after your remorse has fuelled so much good, you will have nothing to truly regret
