@JenM,
Your comment literally put a smile on my face, our relief is mutual for finding another who understands!
Acting in synchrony with who you are in every social situation is truly my most confusing subjects to master. There are so many variables included in each situation and philosophies and findings such as the dunning-kruger effect, it's hard to know when you are on the right path.
A technique I've been using lately is trying to be as present in the moment as possible by asking yourself when you feel lost for the right words is, "who am I in this moment in time?" Helps to center yourself and not worry about whether it's wrong or right, but to just be.
I think being overly aware of external influences acts as a major contribution toward not knowing who you are too. I've been working on bringing forth my own energy and trying not to rely so much on others as I usually do.