Starting over

My back has finally healed.  So now I again have the arduous task of getting the workouts going again.  This sucks!  Seems like every time I think I have FINALLY got IT going, something happens to stall my momentum.   What the %#@%&*&%!  I just want to get a routine that I can stick with.  Feels like I am constantly starting over from scratch.  Why is this such a battle?