problem with right passenger brakes

This started about a month ago. I was driving home from work and I heard a loud noise and saw a cloud of dust. I thought I had a flat tire at first but I didnt have one. So I got home, just barely with no brakes and my dad checked my car and my brake shoes turned to dust, everything else was all burnt up. So we had to replace everything but the drums on both sides. The onlything we didn't replace was the anti-lock sensor on the right side.

It was still making some noise but my dad said it was the front brakes which needed replaced. So two weeks later we replaced the front brakes.The next day I went to leave work and I had no brakes again. So I carefully drove 35 miles home with hardly any brakes.

My dad checked and the bearing burnt out. In the process it ruined everything but he was able to save the drum. Skip forward to last night. I was driving home and I heard a loud rumbling again. I just checked and I don't have a flat tire so I'm hoping it's not the brakes again but it might be. What might be causing this to happen?