What's a simple, cheap treatment for my chronic pain?

Exercise. Try to put up with the discomfort of exercising. It will benefit you in the long run.
Doesn't exists. In my opinion, there is no simple, cheap treatment for any medical illness. You need a careful, thorough examination by your family physician to determine a specific diagnosis and cause for your chronic pain. It could be from diabetes, trauma, infection, and so on. Without proper care, it could become crippling and disabling. Sorry, competent medical care isn't cheap or simple, but it can help.