From what I understand, people with autism or autism-like disorder are just sensitive enough to be depressed or anxious. What I mean by that is that if autism is purely a neurological disorder, then that means our amount of sensitivity in more than just five senses can either lead us to be heavily emotional to a point or none so. So, autism and depression doesn't always go hand in hand, but any bit of overwhelming negativity can lead to it.
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I'm not strange. I'm just drawn that way. That being said, work on your drawing skills already!