I'm close to getting married and I still haven't said the word "Autism" to anyone. Why? First, I'm not formally diagnosed and secondly, because if I were to tell anyone they would think it was a joke. People have this idea (I did at one time too) that Autistic people are braindead and function at the level of toddlers at best. Everyone I told in the past treated me like I had leprosy, as if I admitted that I was actually 12 years old and they were afraid of being seen as a pedophile.
For the record, I have fully disclosed my sensory issues, obsessions, weird interests, anxiety, lack of friends, etc with my partner but it happened OVER TIME when I knew I could trust her with that information. I once dated someone who was almost certainly a 33 year old asexual virgin but I figured it out over time gradually so it wasn't a surprise or shock. If she said that right away, I might have missed out on what turned out to be a valuable life lesson.