If you're not getting the results you need from the expensive doctors you've been seeing, then maybe it's time to move on. You can simply call his/ her office and cancel your upcoming appointments by stating that you are going to pursue a second medical opinion. You have the right to change primary care providers if they aren't being helpful either: I'd check your isurance for in-plan specialists in this field:
Otolaryngologist (ear, nose, and throat specialist)
Otolaryngologists, sometimes referred to as otorhinolaryngologists or ear, nose, and throat (ENT) doctors, are medical doctors who specialize in the diagnosis and treatment of diseases or conditions of the ear, nose, and throat.
Otolaryngologists can prescribe medication and perform surgery for sinus problems, sleep apnea, or to remove tonsils or cancerous growths, for example. Some otolaryngologists also do certain cosmetic procedures to improve appearance.
Otolaryngologists can be board-certified through the Board of Otolaryngology, which is recognized by the American Board of Medical Specialties.
Good Luck. Hopefully you'll find a doctor who will care for your condition so you can sleep better.
YC