Excuse my ignorance, but was this while multi-tabling? (I don't multi-table (yet), hence the ignorance)

If not, and maybe I'm the minority here, but why would you continue to play once you dropped more than 50BB in a single session/day (assuming you derive income from other sources than poker)? I usually buy-in for 25 BB's, re-load once if necessary, and if that drops down to 12BB I call it quits for several hours or the rest of the day.

Whenever I've hit a downswing the key to bouncing back for me is to stop, step back, review, re-read, refresh, and then go again when I feel ready.