IF you got it in good then be happy it's still +EV in the long run and well you're in this game for the long run. So do like Stargrinder said and analyze the hands to see if you indeed played it correctly. If you did and villain made a real stupid play then take note and make it a point to play with him more often as you'll benefit if he is making mistakes.

I have no idea of you history as far as how long you've been playing etc. If you are new to the game you'll learn to work through it. Spoon has written some good stuff on the issue as have others. So read up and well if all else fails go put your head on a door knob for awhile!