Hopefully you're only playing 1/5 - 1/4 of your hands. Your loose opponents are playing more hands. You are probably winning a higher percentage of the hands you play.

Basically:
You must think about it in terms of money not pots. Your loose opponents have a higher "turn over" of hands- so may win more pots, but also they loose as many" so their "success" is far more luck dependent. Their swings will be higher- just look at PT stats (if you have PT) for any game- keep checking net winnings for your opponents every 5 hands or so- you'll see them jumping about all over the place. Your's should be much less volatile.

Ian