To answer your question – no they won’t boot you off their books.
It’s your body and you can do what you wish with it. You are perfectly entitled to make informed choices to refuse tests or treatment. Your GP won’t be worried about money just you. It’s a little disturbing that people think GPs are money motivated when actually they all go to work to do an increasingly difficult job caring for their patients.
The only catch to this is that your GP takes responsibility for the effects of your medication when he signs your prescription. Any essential monitoring tests are a reasonable expectation on his/her part as without them you may take too much / too little and so become unwell. Therefore, if you unreasonably refused even essential monitoring they would quite rightly have huge concern. It’s only about the best care for you.
You really should go and talk to your GP and sort this out. They won’t want you unhappy either.