When I talk to small business owners who do not enjoy their work I generally point out that they are idiots. If you wanted a job that you did not like there were many available to you. There was no reason for you to start a business and create your very own hateful job!
Business owners give up security and accept a lot more risk when they start their own businesses. There should be benefits as well. Generally, what you see is that people who work for themselves usually express more job satisfaction than employees. That makes sense to me.
Another scenario that works is if the business owner is making a lot of money. Many people consider it to be an acceptable trade off to do work they do not enjoy if they are getting a great deal of money.
But what if you are not making a lot of money and you are not enjoying the work? Well who is in charge here? This is your business! Figure out what you do not like about the current situation in your business and fix it up.