I'm sorry you're bummed out by the holidays and crudbucket weather. I think a lot of us get like this... seasonal depression or whatever. I once got into a conversation about it with my grandfather, and he was stunned to hear I feel the same way. He'd never once mentioned it to anyone, thinking he was completely alone with his rainy day blues and needed to suck it up like everyone else probably did.
He brought up my dad, who has Tourette's Syndrome. And that's my spectrum-ish disorder, so I think the crappy weather and holiday stress is amplified with sensitive people like ourselves.
Happy birthday though. If you're bummed out spending Halloween alone... perhaps you could man the door when kids come looking for candy? And for your mom's obsession with cooking, I'm not sure if there's much you can do about it, if you've already tried the logical explanation of "we have too much food on December 26th, honestly." It might be her holiday thing, so you could find a more peaceful holiday by staying out of the kitchen.
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