staying focused (help)

[Dallas Dru]

Over the last year I have been a solid player at the .25nl level and have had extreme success and extreme downfall. I always start out focused and firing on all cylinders but after about a week to a month of straight playing I find myself falling short and making plays that are not winning with –Ev. I have been thinking about this very hard the last few weeks and trying to analyze my game and find out why I am making these horrible mistakes that lead to horrible luck and depressing downswings in my game. I have found that when I am winning I am beating the game at close to 10ptbb and when I am losing and I just getting slaughters, it feels like I cant do anything right.
As I thought about this I have felt that it has to do my mind. I play well for two weeks or so then I relax and let my focus slips away and I can’t grasp it until I lose all of my money. It is like a mental switch in my head telling me to lose my money so I can get focused again. Dammit I don’t want this again so I am asking for suggestions that people use to keep their game on par and maybe a few techniques that I could practice to at least keep my game running on all cylinders.