I'm going through the worst, 2 month long, cold streak of my life (been playing or 12 or so years) so I can relate...

Best advice is take a few days off, clear your head, examine the hands you were involved in, go into your next session expecting to win.... If you don't win, just realize that you've come to a point where you've played enough poker that your un-heater (which was going to happen eventually) is here... I've heard it put this way: "if you haven't had a series of 10 or more losing sessions -despite being a solid player- you just haven't played THAT much poker"..... Happens to everyone eventually..