I just keep right on going, for the most part. Pick myself up and continue. However, a good coping mechanism for me is to be around friends or family so I can talk through it with them, or just feel secure. Being alone tends to make things snowball and I end up very depressed.
The other thing I do (especially if I do have to be alone) is find work to do. I'll clean, run errands, and do other things that require my attention and create a sense of progress. I mean, sure things didn't go as planned but hey! My apartment is really clean! That feels better!
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Yes, I have autism. No, it isn't "part of me". Yes, I hate my autism. No, I don't hate myself.