If you only had one day left to live, and you had the chance to tell one person from your past "I love you," who would it be? How about "I'm sorry"?
When you have as many regrets as I do, questions like this become a game of prioritizing and figuring out the exact quantity of relief that will be given for any sort of situation. Once that's sorted out, then there's a one-or-the-other situation, because generally the very same person I might feel the need to confess an emotion to would also be the same sort of person I'd need to apologize to.
I'm...just that sort of a man.
So! Let's start with the first question, and confessing love. The list of the people I've loved is quite long, so we'll just start with x as a variable. No, no, I actually did know a woman named X and while she was quite nice, I don't actually think I loved her. Though I did love her potato-and-leek soup. So we'll call that variable p.
So! If p is the person involved, then we'll need to take a variable for prioritizing---wait, wait, I've just used p, haven't I? Right, we'll use l, because...that's a good letter. Then we have the quantitative amount of relief that will come from the confessing. Something vowel-y. e. So, it's p (l + e). To obtain q, we need to take the time involved (and time is the most important thing in the universe, so we'll call that a) multiplied by the emotional investment and the relief of ending the investment s. So e = a x s. Are you following me? Good, because I'm only doing this once.
Next, you need to figure out the apology. That's actually very simple. The amount of the bad act (o) minus how much good it did for the person involved (h). Because, really, if I did something like, I don't know, abandoned someone a distance from their city, but it was to keep them alive, then that's a quantity of like 7 - 89. So, the apology isn't necessary. But, if I stole someone's Torchwood card in order to wipe my name from their files without their permission, then that would be more of a 25 - 17. And an apology would be necessary (don't hold your breath, though).
Then, we take the entire situation, leveling the apology versus the love situation, then subtracting the time since I've seen the person (e again). Because while it's important I go back and apologize to Cameca, I'm sure she's probably forgotten me by now.
The entire equation looks something like this:
[o - h] ~ [p (l + e = a x s)] - e.
There! Simple! You can plug in any of my companions, now, and see what I've planned should the situation come up. Not that it will, I plan on sticking it out in this incarnation as long as I can!