Way back in '03/'04, there was a lovely lady who was really into me (citation needed), who I was pretty jolly into myself, and she invited me to her 21st, some sort of Victorian-themed dress-up or something. And this freaked me the fuck out. The costume part was an obvious obstacle to focus on, but even after I'd decided I wasn't bothering to dress up, even after it was too late to buy or rent any costume, I just kept freaking out more and more, wrapped in a dark, tightening shroud of stress. It got to the point that it was too late to scrounge a lift there with anyone, and then to the point that I was ignoring calls from people checking that I was still alive and on my way. I was feeling absolutely awful when I finally broke down and sent a bare-minimum reply saying I wasn't coming.
Naturally, this looked quite mean from her point of view: I'd gotten her hopes up by saying I'd come, then dashed them by not only failing to do so, but by giving only a terse rejection for no apparent reason a few hours past the last minute. Dealing with her subsequent (probably justified) wrath over the following months added enormously to my stress too, especially because it was so hard to explain (and, in hindsight, she was a bit of a dick too). But in that moment, admitting I wasn't coming and shutting myself off from humanity was the most relieving thing. It was like I had no choice in the matter, some autonomous part of my brain had already made the decision for me, and in fighting it I was just stressing myself out horribly, until I stopped fighting and accepted my lack of conscious self-control over the matter.
I think that was the first time that happened to me, and it was very uncomfortable in a lot of ways. It still happens a couple times a year, when I genuinely want to go somewhere and be with the people there, but some part of me just refuses, and the internal conflict just shuts my whole brain down until "I" relent to "me", or whoever the relevant actors are. I tend to get a feeling a day or so in advance now, warning me that I'm likely to shut down like this. But that's not much help; I just begin to imagine how I'm going to disappoint people this time, which compounds the stress, which makes me less comfortable about the whole thing, which makes me worry more about letting people down, etc. And if anyone asks me what's wrong or tries to be encouraging, it only makes things worse by highlighting the state I'm in and the fact that I'm not successfully hiding it. The only relief I seem to get from this is the point when I finally admit to myself that I'm going to disappoint people. It's not great, but at least it makes the cycle of panic stop. And being aware of this now, I feel less distressed by it than that first time in 2004; it fills me with stress and regret now, rather than completely freaking me out.
This is far from a major mental disorder (I hope), and it really does only affect me 2 or 3 weeks out of every year, but it is pretty damn inconvenient, not least for the people I screw around. Most often I end up cancelling a plan with one person, maybe one group, but this weekend, for example, I dropped half a dozen plans, some quite important, some merely enjoyable (most likely very enjoyable), involving many separate people, and I don't have a good explanation why. At the risk of contradicting my own warnings, and bearing in mind that few of you will know all the relevant facts I haven't included here, I'd be interested to hear if anyone has any possible explanations. Does this sound like anything anyone's familiar with? But more importantly, if I ever do this to you, I apologise, it really isn't anything about you. It isn't really anything about me either; it's just the other bit of me. It sucks.