Hey theoneguy - quit stealing my name 
Here is a tid bit of info that I hope helps you. The struts in a vehicle today take the place of shock absorbers used in many trucks and SUV’s built currently and years ago. What that means is they control the extension and compression of your coil springs in your suspension. allowing the vehicle to stay more level while traveling on imperfect roads. That being said when your struts start to wear out they loose the absorbtion aspect of the shocks soooo your springs no longer have the limitation on their movement, in other words they can loose contact with the road surface when you hit a bump. This jostles the tires quite badly leading to a harsher more “springy” ride, the wear on the tires become readily visible in short order as well cupping and un even wear are almost always present. Inspect your tires for irregular wear patterns, if the wear is present then yes it MAY be time to replace them, if you have never replaced the front struts you may want to replace them at the same time. save yourself the trouble of having to replace them probably in the near future. BUT be sure that it is the struts that are the problem before you spend the $200+ to replace them. there could be other issues that can cause the problem you are having.
Hope this helps your car, if not, you can invest in a set of skies in place of the rear tires :P.
best wishes