Rear breaks

I have a 2001 Chevy Cavalier, With ABS. Starting winter my rear right tire started locking up and causing my car to bend down to the right. It doesnt do it all the time, but does do it often. It only does this when i am stopping. And once im stopped and let off the break my car pops back up from being bended down and makes a crack noise. My dad took my drum off to see what it could be and i still have a quarter worth of shoes on the back and my drum seemed fine, but my breaks were pretty spreaded out, so he fixed it so the drum went on way more easily,and that was a week ago and it hasnt done it since, except its starting to do it again. what could it be?

I would look for a sticking wheel cylinder on that brake. The fact that the shoes were spread indicates that the cylinder pistons are not returning to the fully retracted position.

The best approach is to get a complete brake overhaul on the rear axle. That would include new wheel cylinders, relined brake shoes, rear drum turning, and new hardware. That should alleviate your brake pulling problems for another 10 years.

First of all can we please establish that a car has brakes. Brakes, not breaks.
I don’t mean that as a personal dig, it is just that it happens over and over again on this site and can we at least establish this one thing.
As to your car. Your dad apparently loosened the rear brakes. That helped for a while but now the problem has come back. You have a stuck rear brake cylinder. The part keeps pressure on the brake shoe until the shoe fails. Your dad’s solution just bought you time. Rebuild or replace the rear brake cylinders and replace the rear shoes and turn or replace the rear drums.

The thing that bothers me is, you say the car bends to the right. Then unbends itself making a cracking noise. I’ve seen brakes lock up but not cause a vehicle to bend in any direction.

You might want to inspect the rear suspension for rusted/broken/worn components.