How do you repair a bent A-arm on a Ford Taurus 2001?

Okay, so I'm not even so sure it's an A-arm...It's a bar connecting the two back tires, goes across. It got bent from someone who tied a rope to it to pull me from a ditch. Apparently, that individual didn't know a hook existed for that purpose. Anyways, it's bent, and the car swerves all over. Could barely get it home. What is this part?!