I think this sounds a lot like burnout and the sooner you admit it to yourself, the sooner you can think rationally about it and address your psychological needs and start feeling somewhat better. You probably need a total break from it for a while.

I think that almost any particular sort of work can be either wonderful or terrible depending on a lot of other factors:

- autonomy

- relationship with coworkers/management/clients

- work/life balance (cliche, but there's really something there)

- possibilities for learning new things in the course of the work, etc.