Discription of Events: They were going 40 in the 55, constantly speeding up and slowing down. I thought I lost them one on 79 and I passed them. I was wrong. They sped up and looked like they were going to pass me but ended up right beside me looking in my window. They eventually passed me, and were about a mile ahead. I ended up passing them again after I saw their brake lights plenty of times. The entire time my cruise control is on at a constant 70mph. I felt extremely unsafe.