For people on the spectrum masking is basically roleplaying a "normal" person, by learning behavior that is associated with not being singled out as a weirdo.

This takes a lot of processing power and constant vigilance in order to not drop the mask which is quite exhausting.

Here is one study looking at the connection between neurodiversity and substance use: https://pmc.ncbi.nlm.nih.gov/articles/PMC3965675/