I'm in a similar boat. Not as bad as your experience sounds, but I would definitely consider it an unchallenging job that leaves me feeling more stressed than anything. I have lots of ideas I want to pursue in my free time, but I know that if I get involved in a project it will make time go by quicker and I'll just have to be back at work sooner. Everything I do in my off time is designed to make it feel as long as possible. I haven't read a book in months. Sometimes I don't even want to watch TV because it's too entertaining.
God damn that's depressing to write down.