Here is what acting is to me: Pretend.
I've always said (and I stole this from someone, who I can't remember) when I get onstage I put on a funny hat and trust to luck.
I'm not much into actors that "live" their characters, in all their smelly, depressed, antisocial glory. I don't particularly trust them onstage, and I've noticed that these actors will throw you under the bus for their own ends. And gladly lap up the applause at the end.
If you are working through something, please don't do it onstage. The theatre is not a couch and the director is not a therapist. If you are feeling something, great. I feel things too. Deeply, crazily, intensely. Until the scene is over. The I go into the greenroom and play scrabble. And at the end of the show, even if I've just lost my family in a holocaust, the kingdom is on fire and my life is in ruins, most likely all I am thinking of is how much I crave a tub of chicken liver and a nice bagel from Jerry's.
I used to be embarrassed that I wasn't intense enough. In acting school, you knew the people who took it seriously, they were wild eyed, unshaven wrecks who burned with fever onstage, and couldn't cope with their job at the donut shop offstage. I never felt legit, until I started studying in England, and realized that THOSE guys manage to stay fairly clean, and sane. My feelings of inadequacy absolutely turned around in the pub backstage at the National Theatre of Great Britain, when mere minutes after a bloody, crazy, intense INSANE performance of Titus Andronicus, Tony Sher was gleefully showing off his new pasta maker, not an angsty wrinkle in sight.
Feeling the truth of the scene is great, but please, please, PLEASE, you need to stay in control! No re drawing the choreography because you feel like doing something different.
Otherwise there would a lot of dead wispy ingenues at the end of a lot of Shakespeares. Hmm... On the other hand...