I live in Fear of Downswings (and TILT!!)

I have been playing online (and homegames) erraticaly for probably a couple of years. I feel I am only just now beginning to play marginally winning poker--although maybe I am being too hard on myself. In the past I have tilted after minor downswings and so I have restricted my daily play to 1 hour a day. Playing 1 hour and focusing on playing as perfectly as I can and not tilting at all in that timeframe in hopes that my discipline will improve. So far this is going well. However, I am living in fear of that 200bb downswing or even 50bb downswing that might be just around the corner. I keep repeating to myself, just try and make the right decision no matter what.
Do any of you live in fear of this occurence?
-g