Please don't give up the fight to feel normal again. If you do give up the fight and try to manage without any treatment, at least try to think of the damage to your heart. If your mood, your driving, your work, your social life and relationships don't seem to be affected...you can still count on heart disease and/or stroke to knock you down.
As I said in previous posts there are other options to the dreadful "Darth Vader" mask. But don't quit too early if you already have possession of this device. You might find yourself getting used to it right about the time you're getting ready to throw it out the window.
Please contact your medical equipment company and communicate with them as much as possible. They have numerous types of masks and nasal pillows that you should try. You owe it to yourself, friends and family to try as hard as possible to get the proper amount of oxygen and sleep.
If you absolutely cannot take the CPAP then talk to your physician about a referral to an otolaryngologist (ear nose and throat doctor). This physician will let you know about what options for surgery are the best.
I've seen great results in patients who decided on a combination treatment. Having surgery and then wearing a CPAP at a much lower pressure has been a success with some patients. Also, surgery in addition to wearing a mouthpiece has been popular. You might only need one treatment but if your one treatment isn't working then consider looking at all avenues.