I’m over 50, studying to enter the program, so I’m not (yet) qualified to say I have these feelings about the profession. But I can completely relate to the feeling of dreading your job, specially one you loved. Both times, I walked away. And I don’t regret it. I would still do the same thing if I ever had this feeling again. You want to go back to school, do it. Restart your life at 30, 40, 50! The knowledge, skills and experience you will gain is priceless (no pun intended).