Is there demonstrable proof that generalized anxiety disorder exists and is not a ploy by drug companies?

...or vice versa

There is a set criteria for GAD established by the American Psychological Association that is based on research with the disorder. If you are looking for legit research go to your local university library and do some academic searches (the internet will not help you with this). I think the main issue is that everyone is looking for a quick fix rather than doing some serious therapy and soul searching and drug companies feed into that. I've also known and worked with some people who need meds, so I see both sides.

Anxiety is a SYMPTOM of a problem, not the problem itself. Anxiety is an abnormal state of being caused by an internal problem. It is not the disease, but a symptom of "disease"
Your HMO wants you out of there quickly and cheaply, drugs being easier than blood tests and proper diagnosis.

Yes, anxiety/panic is real - heart palpitations, weakness, fear, nerves are real symptoms, but in many cases, especially in women who have used birth control, it's a dysfunction of the hormonal system, not a mental problem. It's ludicrous to blunt the brain with drugs, rather than re-balance the body.

In general, feelings like anxiety are created by physical processes in the brain. It is not credible that the process of generating anxiety will always work correctly, when we know that every other physical process in the body is subject to failure or deterioration.

In many cases anxiety has a cause in the social environment, but it is also true that many people experience different levels of anxiety from the same situation...

So I think disorders like GAD are feasible and credible as medical conditions, and they are not just symptoms redefined as illnesses.

However, the most effective treatments for GAD are talking therapies, with drugs for short-term crisis periods. So people can learn coping skills and make lifestyle changes that help them deal with anxiety (or have less anxiety), and that is in fact a standard treatment for GAD.

I had a doctor who thought the exact same way and he ruined my whole high school life because he didn't believe what I was saying. People who don't have a problem with anxiety don't undrstand how much it affcts those who do have it. It is a daily struggle, even with medication, to lead a normal life. Anxiety problems can ruin lives, and people who suffer from them deserve to be taken seriously!