Monday Morning Morals Question - Is it sometimes worse to apologize?

So this post requires a little back story, which I will get to, but first allow me to reintroduce myself to the cyber-world.  I know, you've all missed my rants terribly and I am sure you've been starved for my witty banter and cheeky commentary, but for at least today...I'm back!
And, I also know that it's Monday night, not morning, but the fact that I'm here on a Monday at all is, frankly, one step in the right direction -- and I went to yoga today, so that should count as another step in the right direction -- so I'm celebrating my small victories in this ongoing battle between my good intentions and inertia.
So here's the moral quandary...is it sometimes better to forgo an apology for events in the distant past and simply let things be, or should we seek out those we may have wronged and apologize for transgressions from long ago?
I have my superhero cyber-vision on and I can tell that you're all wondering - what the hell is she talking about and why would I care?  So allow me to explain.
This evening Alex and I were talking as I tucked him in, and he made a comment about a kid at school who eats his boogers (yes - I, too, gagged when he mentioned it), but then he went on to say how all the kids at school were afraid of "Jace Germs" and were frantically running around shrieking "Watch out for Jace germs" and the like. (Jace is apparently the kid's name...I've never heard that name before either??)  But I was taken aback by the comment, and I remembered something from when I was a kid that I am really not proud of...
There was a girl at my school named Leah.  For whatever reason that I can't even remember now, she was kind of an outcast kid.  She was always a bit different, and to be fair, she wasn't very nice herself, but when we were in elementary school, kids were just plain mean to her. -- 1970s  throw rocks at each other politically incorrect MEAN kind of mean.
They'd call her "Leah Pee-ah Diarrhea" and run away from her on the playground shouting "SPRAY YOURSELF WITH LYSOL."  There'd be comments about her mom and her intelligence and anything else you can think of.  Mean, mean, mean, mean, mean!
And while I was never the instigator, (and I don't specifically remember calling her names myself), I know for sure I never stood up for her, I never said stop, nor did I even just quietly say I was sorry when no one else was looking.  I didn't do anything, which as far as she was concerned, was probably just the same as me having done everything.
So I told Alex this and related it back to Jace, and then I told him that I felt bad that I had never apologized to her.  I said "I don't want you to be 40 looking back at your life wishing you hadn't been mean to this kid or some other.  Live your life in a way that ensures that you will never regret what you have done."
And then I told him that I was going to apologize to Leah via Facebook tomorrow, which he seemed to think was a good idea.
But after I left his room, I started thinking about it -- who is this supposed apology for? Leah? or ME?  If an apology isn't going to make the wronged person more "whole" (or at least make them feel a little better), what's the point?  When it comes down to it, really the only person who might feel better from an apology is ME, and how selfish is that, really?
Let's face it, even I'm not so self absorbed as to think that 25 years later, Leah is still nursing hurt feelings over what I did (or didn't) do to her on the playground in elementary school.  Realistically, she probably doesn't even remember...and if she does, she's probably just as well off thinking we were just a bunch of assholes rather than letting us off the hook now.  She doesn't need to be reminded of it all by me in my self-serving desire for catharsis. She probably just wants to move on -- and who could blame her, really?
So I've decided that I'm NOT going to apologize.  I'm just letting bygones be bygones - water under the bridge and whatnot. And I'm not giving myself the satisfaction of feeling like I made some big magnanimous gesture to set things right from the past.
But at the same time, I'm also denying her the opportunity to know that someone (i.e. me) actually did care about how she was treated.
So it's a double-edged sword, but I'm sticking with this plan for now.  Is that wrong??
PLEASE, JUDGE ME!