Ask yourself the question, "Why do I get mad?". There must be a reason. It might be that you get aggravated by the pressure of the job, or by the attitudes of the clients. When you find out what the answer is to that question, you can establish why you hate your job. From there on end, you can work on the problem.
Most of the time, it's just that we have to fix our attitude towards something. Remember, you are the only one who decides whether or not you're going to enjoy your day. You're the only one that can allow something like a lousy job to make your life miserable. Try to make your job more pleasant (stop being angry when you work) and while you're doing it, study to do something else (correspondence of part-time off course). That way, you're actually solving the problem instead of just sitting with it, not knowing what to do with it.
They lied. You need to interact with clients, co-workers, potential clients etc. The clients don't like your work, not because it's bad, but because it's not the picture that's in their mind. Communicate more with them so that you get an idea of what they want and what's in their mind.
It was the college faculty all telling me this before I entered and picked a course and I believed them. I know people aren't going to take the first thing I make for them but the endless changes feels like a waste of time. I feel that "if you're not liking anything I make then you make it yourself"