I was called "a catch"

I got offered a job doing experiential education with 4th -12th graders out in california. They called me "a catch" and said they would be honored if I went to work for them. It would have been a perfect job for me 4 years ago - but it you start teaching at 9am and teach until 9pm.

I can't do that. There is no way my immune system would survive. So I am looking for a plan C. And I have to tell this nice company and nice man that I can't work there because I am too sick. I'm not so much angry but honestly, just sad.