> But as for immersing yourself in past guilt...I find that this happens to me, and my rationality is that I deserve the guilt from my failures and misdeeds. That if I "live in the now" I am doing a disservice to those I may have wronged (even though they may have completely forgotten whatever it was by now and moved on).
> ...
> But it feels so selfish when I apply this mentality to my transgressions upon others.
I can relate.
I think that a certain amount of guilt is good, but it's not at all obvious how much is optimal. The guilt in itself doesn't help the ones hurt. I suspect strongly it's a lot less than people frequently immersing them-self in guilt employs though. Just accepting that it's a very hard optimization problem in a very uncertain domain is probably a good idea.
The appropriate amount of guilt is just enough to change future behavior. That is assuming the remorsed misdeed actually was our fault and not due due to circumstances out of our control.
The less clear the situation around the misdeed is, the less guilt is helpful. If it's hard to pinpoint what we actually could've done differently it's hard to induce change.
The best apology is changed behavior, etc.
Repeated micro-guilt is probably better than longer sessions of self-loating. (assoc.: spaced repetition) (Again - assuming high certainty about the nature of the misdeed - meaning also an initial analysis of the situation have been done)
Sometimes it's best to simply talk to the one we suspect we hurt :) Not always easy though.
In general it's frustrating how ineffective rationalizing such things is - personally I haven't found a better approach though.
A final assoc: one-line quotes like "Live in the now" is highly (lossy) compressed advises.