For me, it’s pretty boring.
If I’m talking, it just looks like I’ve lost my train of thought. Totally normal and happens to everybody.
Sometimes I’m visibly startled and at worst I’ve gasped out loud. Waking up with no idea where you are? Super scary. It can usually be explained away as “I thought I saw a bug!” though my friends do think I’m deathly afraid of insects 😉
My shifting tastes in music, clothes, and food are just “trying something new”. When my opinions change, “I’m exploring both sides of the topic to try and really understand it”.
Under stress it’s more noticeable, but even major mood swings can be explained away. “Not feeling well”, “ugh, migraine”, “I’m drunk” and “PMS” are my favorite white lies. And there’s always old reliable, “Oh, I guess I’m more [emotion] about [topic] than I realized! Funny how that goes, right? How is [redirect]”.
It’s worked for over twenty years. It’s not that people are stupid or that I maxed out my deception stat in real life. Honestly, most people are preoccupied with their own problems. The world’s a little shitty right now, so it’s not surprising, and it works in our favor.
The few rare observant people who notice the posture, accent, tone or slang changes are far too polite to mention it. What are they going to say? “Oh, did your personality just completely change? What’s that all about then?”
DID is a covert condition, or people would know a lot more about it 😉