Lack of enthusiasm

I am accused of a lack of enthusiasm at work.
Well, yes. I'm not enthusiastic about this job, or work in general. Isn't it enough that I do it? Is this not enough of a compromise? A concession to the capitalist system?
I have a love/hate relationship with work. When I had none, I longed to be useful to someone, anywhere. When I am working full time, I feel my life blood being leeched away from me in to my job, and resent its intrusion in to my otherwise pleasant existence.
During these periods I tell myself that if I spent an equivalent amount of time directly maintaining my existence - growing food, for example - then I would be happier. It's the fact that I'm a wage slave that I detest, not the fact that I have to work at all. Don't tell me you haven't had similar thoughts.

Lacking enthusiasm. This is true. I try not to, but occasionally I turn up late. I am not focussed, because I have other things to think about that are more interesting and, in my view, important. Sometimes I weigh up the options of going out and being tired at work the next day, or staying in and being energised, and I choose the former. I need to see people more than I need to do a good job.
Is this selfish? Perhaps it is. But perhaps it's just that my job entails more responsibility than it used to, and I'm not prepared for it - nor do I have enough passion for my job to let it affect my life above and beyond the hours I spend there. I'll give them the time and energy I'm paid for and not an iota more.