I managed to tear my hamstring badly (I used to be a sprinter) about 4 years ago....
basically the healing process involves not putting it under too much strain, but to build the muscle back up by doing small excercises every night with weighs on your ankles....
to be honest, i just went straight to the physio and she recommended all that i did and i imagine a tear is different from a pull anyway!
So yeah, don't expect it to heal overnight...and have the patience to work at it bit by bit, but above all seek advice from a physio and do as they say!
I was fully fit about 3 months after the tear i think, although it WAS quite a long time ago.....