Workin' it out

Several times over the last six months, I have had an overwhelming feeling of sadness when thinking about how my last living situation worked out. This has intensified over the last few days; every time I have a birthday I reflect on who I spend it with—who I want to spend time with versus who I really don't want to spend time with. I've been running the last months that we all lived together through my head over and over again, trying to figure out when the communication broke down completely and how I became the total odd-man-out. Did I do something horrible that I don't remember? Am I completely unbearable to live with? Had our friendships run their courses? I can't for the life of me arrive at any kind of solid conclusion. I'm thinkin' either A) they both were incredibly patient on the outside but on the inside really hated Hank and it got to be too much (this is entirely possible since he is a huge pain in the ass), B) they got sick of my mood swings and quietness (12 credits, an honors thesis and two jobs is likely to take a bit of the wind out your sails), or C) they hated Brian, or my consistent reflecting and advice-requesting on our relationship. Likely it's secret option letter D) a combination of all these things.
As I'm putting this all down in front of me, I realize that there was decent reason for them to be sick of me and happy to be rid of me and move on to a happy life together. I can't blame them for pulling away, or letting me pull away, or not being the first to take a step to improve the communication. On the other hand though, I am a bit indignant. I am still angry/stung/hurt at the fact that there were no graduation well-wishes, no acknowledgement that the intensity of my semester and previous five years had paid off. And after writing everything above, if any of the letter options do account for the fact that we are no longer friends, I wish they would have told me that I was bothering them so much that there was a possibility, even a liklihood, that we would no longer be friends.
I don't absolve myself of the responsibilty either. I was too proud/indignant/hurt/in denial to make the first move to resolve any communication problems. And I did make the decision to move out on my own and separate from the arrangement as it had been for the previous 18 months (although I'm sure that made everyone happy).
So what to do now? It's been six months with no talk, no texts, no fb or myspace messages, no tweets. And I'm having a hard time letting it go. I have dreams, memories etc about the girls, even the dogs. I've been considering writing an email and just letting them know that I miss them and that if they're interested in a friendship then I'd be thrilled. But for some reason I'm scared. Of getting shut out I guess. Maybe our relationship really did run its course for them, maybe they got everything out of me that i could give them. Most of me still really doesn't want to be the vulnerable one, since I am still really hurt and angry at the way things ended.
Anyway, I guess the point of this is just to work it out...to straighten things up in my head and come to some acceptance or some place of understanding. If you have any advice, I'd love to hear it. I have the sneaking suspicion though that this is one of those things I'm going to have to let go of and get over. Which I'm horrible at. Eek.