Sounds very familiar.

I don't know how people can just throw themselves into social situations and keep the same pace going for hours on end. I suppose it's because they're fairly relaxed in that environment so they CAN sustain it and are willing to chat throughout.

I am very circumspect with my face to face socialising, wonder what to say and when, and worrying about how it will be received. I have so much anxiety invested in each sentence is why I take so long to talk and why it's so hard to maintain.