I just want to say that I can relate to your position and frustration. I am stuck in a field I don't want to be in anymore but I've invested the last 10 years into this field and have few other skills to offer. I would have to take classes in another field in order to switch directions, but I am older and taking classes while working full time is very difficult for me.

That would be my only suggestion, as has already been mentioned - classes in a field of interest. There are short courses, even two-month certifications, you can get online that you can do at home at your own pace. Something to look into, if you're thinking graphic design or advertising.