Why do I have such sloppy steering?

1.) have a master front-end machanic look your car over. If you haven't done much front end work, your guessing that everything is "O.K".

I changed my power steering fluid and had a more solid response.
It may have just been "topped off" from day one & never changed. Wheel bearings, tires, power steering pump worn out, steering box has excessive wear, beyond tolerances.
May your trouble shooting be successful,
Kruzz