My rear driver side wheel is moving side to side when I drive, it looks pretty bad. It makes no noise, all of the lug nuts are tightened, the brake disk doesn't budge when I try to move it. Any suggestions on what I should do?

 

check wheel bearing its prolly gone. Also I would check the few other suspension components that are there for play. But I wouldn't drive it until you figure it out.

 

Check camber and toe arms, they could be loose. And yes do NOT drive like that, it is unsafe.

 

Jack it up, grab the top of the tire and pull/ push to see if there's wheel bearing play. Then pull the wheel and check your arms, just pull on them and you'll find the problem.