"the therapist's only purpose is to make money and that the therapist actually does not care about me or my problems at all."
Right. They don't care about you or your problems, they care about doing their job which involves providing appropriate therapy and services for their patients based on the patients' symptoms and needs. Caring for a patient just isn't practical.
Your friends and family probably care about you more than a therapist. The therapist can probably help you better than your friends and family.
The therapist goes to work to make money like everybody else that works. Yes, they probably care about their financial well being more than they care about a patient. They aren't your friends or family.
"ADD doesn't exist, that it was manufactured by the pharmaceutical industry."
So people behave in certain ways. That behavior can sometimes get in the way of a productive life. When somebody's behavior is troubling in some way, and consists of specific observable traits, it is often identified as disorder for the sake of amending those specific troubling behavioral traits through medicine or therapy.
Does ADD exist? Yes, the term attention deficit disorder exists for the purpose of classifying a specific set of behavioral traits that may be seen as troubling.
Manufactured by the pharmaceutical industry? (to sell drugs)
Maybe. If you get somebody to believe their behavior is troubling, and then get them to believe they should buy drugs to treat it, you're laughing all the way to the bank.
If somebody believes their behavior is troubling and meets the criteria for ADD, they can seek treatment to help amend their ADD specific behavioral traits. Pharmaceutical companies will make money if people buy drugs for ADD, yes, and people that believe their behavior is troubling might feel less troubled after taking the medication that is designed to amend specific behavioral traits. Everybody wins, unless of course the treatment does not amend the patient's troubling behavior.
Your friend is not being helpful or caring. I think he's trying to help, but just in a misguided way.
I think your post triggered me. :P