I have to deal with many people for work, which is harder in the office. I still take my time out and not interact with people, whether that be going to lunch by myself or just putting my headphones on. Sometimes, I find talking to people who aren't annoying me (for whatever reason, irrational or rational) helps settle me.

Someone on my flist mentioned a "Have Done List" and it's been a lifesaver during those days where I feel deeply unmotivated!