How often do you give yourself the silent treatment?

Only when there are other people around.

When I am here.

hahahahaHAHAHAHAHAHA - good one!

I had to give up on doing that.  Every time I'd get angry at myself and tell myself I'm not talking to you anymore, I'd quickly start pestering myself in an effort to make me say something.  The longest I lasted was 3 hours before I made myself say something.  Soon it became a game trying to see which one of us could make one of us talk first.  One time I got myself to break the silence when I was in a public restroom (talk about embarrassing yourself).  Finally it got so bad that I made a vow with myself - no more silent treatments.

never

When I begin to feel that little twinge-y feeling, I know it's time to shut it down.

Not very often at all. 
I am far more likely to be seen and heard giving myself a round of applause.