Ant, I"ve a few things things to clarify from our previous posts on this subject.
1) Going back to your first post, s**t happens, you"ll just have to get used to it. Content yourself with the knowledge that if that same situation comes up again, you"ll be a winner in the long run.
2) As for my comment about bluffing, it doesn"t really relate to this post, but was intended as a genuine attempt to give a bit of useful advice. Think back to those sparsely populated,but competitive, events at the Grosvenor Yarmouth. I can think of 6 players, including myself, who picked-up on an almighty tell you give off when you"re bluffing. Clearly, I"m not going to give it away on here(I"ll PM if you want), but it was the main reason why I suggested having a rethink of the hands you play.
3) Justifying something by referring to Harrington or Sklansky is asking for trouble. (a) most of your opponents will have read those books as well, so will be able to spot someone playing by those rules (b) If at any point during a hand your process involves "What would Sklansky/Harrington do", that suggests you really don"t know where you stand and you should make a sharp exit.
4) If concentration is a problem, then don"t play at all. Try setting yourself a time limit, say 1 hour, then turn off any distractions and play for no longer than the time you set