I have been with one of each, and I found that I do better with people on the spectrum.
This is based mostly on the fact that although I have made great strides as far as communication goes, I still feel like I have to be psychic to be able to understand an NT. Plus the NT ex-girlfriend cheated on me.
Granted there still can be obstacles in an ASD-ASD relationship, depending on what level of functioning the two people are. For instance, I am very high-functioning/mild AS who can handle routine changes rather well, and has overcome his sensory issues. I think for such a relationship to work, it would work better with someone with a similar level of functioning.
For the records, I haven't had a single meltdown in almost 11 months as of today.
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Who’s better at math than a robot? They’re made of math!