I know lots of people in theater. Some are very dramatic (in real life) and some are not.
In my personal life, my mood swings can be kind of epic. (Just ask my dear husband.) Luckily, thanks to some excellent drugs (better living through chemistry), they are not so close together anymore.
And yet, I don’t think of myself as being overly dramatic.
I’m certainly not the type of person who tries to create drama around myself. I believe life brings us all enough drama anyhow, so there is no need to create extra.
I have been told by people that when they first meet me I come across as aloof and sometimes a bit (or out-and-out) scary. And truthfully, I am pretty much okay with that. I want a chance to watch people in action before I choose between being friends or acquaintances.
When I am in a show, during performance, I tend to go off into a dark corner (literally) to gather my thoughts and emotions and energy. I have a need to conserve those things for my performance.
I have this need because I don’t want to feel I’ve failed an audience and/or the material.
This is not altruistic on my part. I will absolutely beat myself up for any perceived failure that I feel I personally could have avoided; and I don’t like myself for the failure or that I am beating myself up over it (and the circle goes round and round).
I didn’t used to be like that. I used to dick around backstage as much as anyone, and I don’t recall when things changed.
On the other hand, as a performer, you also need to be very aware of your environment during a performance – so you need to feel the emotions, but you also have to keep a part of your brain cool, calm and collected ready for whatever happens on that stage. You have to be ready to think on your feet in case something goes wrong.
Performers are living breathing emotional dichotomies.
All this doesn’t mean that I don’t enjoy doing theater. I do. I truly enjoy the people I get to work with and I enjoy the work. I even enjoy some dicking around.
I wonder if most performers have a pot of boiling emotions that they keep the lid on until they need to draw on them for a performance (or that they sometimes let bubble over from time-to-time in real life). And how many are good at focusing and problem solving.
Thoughts?

Sounds like you’ve reached that greatest level of understanding about performance: the difference between
the amateur the pro. The amateur works until they’ve got it right; the pro works until absolutely NOTHING
can possibly go wrong. Makes for a ton of beating yourself up, but the performances are so much better.
That at least is my hope. I just wish it could be accomplished without the beating; I just never learned another way that pushed me through.