Hi Jono! I don't usually ask for advice like this, but apparently, I'm the only one on the internet who's ever had this problem! You can imagine my state of panic. So hopefully you'll know what to do, because I sure don't!
Anyway, my problem is that my boyfriend and I broke up about a month ago. He did the dumping, but I'd certainly been thinking about it for awhile—we just weren't a happy couple anymore. It was a long and serious enough relationship that the breakup could be called a biggish life transition, but not so much that I'm completely, utterly lost and devastated. In fact, when we broke up, I think it alleviated a lot of stress for both of us.
He always said that if/when we broke up, he didn't want any contact with me. But now that we've broken up and he's followed through, it sucks. It's not like I'm pestering him constantly, but the few times I've tried to get in touch with him, I've been ignored, unfriended on Facebook, etc. I don't know if it's a pride thing, a closure thing, a hurting thing, or what! We were best friends before we were a couple, and now, I wish we were on, if nothing else, an occasional status-liking, "hey congrats on pre-law" texting, semi-friendly basis. As much as I feel over him, I just miss him. Please Jono, use your insightful maleness to tell me what to do!
I like when I get to tell a letter-writer what she wants to hear, Sparkler. Sometimes I'll get questions like "This boy keeps texting me and brushing my hair and trying to kiss me on the mouth, is there a chance he likes me??" and then I get to say "Yes! Mazel tov. Go now, and have many wonderful babies." Unfortunately, this is not one of those times. I can't in good conscience tell you what you're probably hoping to hear, and any babies that result from this situation will be purely coincidental. That's not to say I have only bad news for you; I just can't tell you that your boy will come around and decide he wants to be friendly again.
And I know that sucks, but at least he didn't just spring this on you out of nowhere, like an unexpected springy-snake cruelly concealed in a can of mixed nuts. He did give you advance warning that this was how he'd want the breakup to go. Evidently he had his reasons, and he had them back when you two were on good terms—this isn't some wild post-breakup overreaction he had while writhing around on his floor in angst and laundry. Whether that makes his decision more or less final, I'm not sure. On one hand, he was clear-headed when he decided he didn't want to stay in contact with you, so maybe he'll stand by that decision. On the other hand, maybe his Beep Boop Robot Logic that made sense at the time won't actually hold up against his real feelings once he starts to miss you. Either way, you have to respect whatever reasons he has.
You did list a few possible reasons for why he'd want this—pride, feeling hurt, a desire for closure—and I think closure is the most likely reason. It sucks to have a relationship plod on long after it's failing, like some embarrassing zombie, particularly if it was with someone you liked a lot. Ending it probably wasn't easy for him, especially if you two were BFFs, and I imagine he just wants to put this whole ordeal behind him.
Full disclosure: When I was a horrible teenager, I was always bad at letting people end things gracefully. I'd be like "But you said you'd love me forever, and it hasn't been forever yet! Please direct your attention to this calendar and spreadsheet I made." But no matter how much I moped about how this relationship was important to hold onto for some reason, time invariably proved me wrong, and so did distance, and probably any other physics variables you can think of. Trying to cling to a friendship when the other person doesn't want to only prolongs the terribleness. This could even be good for you; you had a breakup that was amicable and mutual, which is much better than if you'd broken because of a really ugly fight, or because he made out with your sister, or because he turned out to be an international jewel thief. At least you still technically could be friends in the future, which is more of a chance than some couples get.
I don't mean to sound insensitive here. I know he was your best friend, and that this situation makes you want to grab him by the collar and throttle him and go "ARGH BE NORMAL AGAIN," but that option is not on the table right now. He chose to opt for closure, and it might even make it easier for you to stop missing him if you aren't talking for a while. For the record, I would never deal with a breakup by unfriending and ignoring someone; I think that's a bit extreme (my preferred approach is to groan loudly and repeatedly until people are forced to ask what's wrong). But what I think doesn't matter, because you weren't dating me, unless I have some kind of super-amnesia. Your boy wants what he wants, and you have to respect his decision, the same way you'd want a guy to respect yours if you told him to keep his distance.
I don't think he's going to avoid you forever or anything like that; I just think that everyone handles breakups differently, and he prefers distance. You've let him know that you still want to be friendly; now the ball is in his court.