Okay, first of all, don't start screaming at your players in team talks. It only makes things worse (just like real life). Keep team talks as positive as possible. However, if you find your fall-off is due to one or two players seriously underperforming, let 'em have it in the media.
Secondly, tweak your tactics. No team plays exactly the same way game in and game out because then they become predictable. In my current saved game, I'm juggling to keep Farsley Celtic from going down in the BSP, and I juggle my tactics fairly regularly. The down side is that the players might not be as cohesive as I'd like, but the upside is that I keep opponents off balance.
Thirdly, bring in some of your reserve players if they're any good. It might turn your season around and it will also grow your bench.
Fourth, if your schedule allows it, schedule a friendly against a lower level team. Beating the snot out of a weak team will help perk up morale.
Fifth, if none of this works, fire one of your coaches. It sometimes helps and in any event it will make you feel better.
Good luck.