I was given a full face mask by the sleep clinician, because I had an issue in the sleep study that she had not seen before. Upon exhaling, a flap of tissue in my air passage would slam closed and block my exhale. It was rather abrupt and severe. She slapped a full face mask on after that so she could get the pressure number. It was strapped on tight.
So I used the full face mask for a few months, as best I could. It had to be clamped to my head rather tight, and I learned to accept it by thinking of it as a lifeline of air to me , as if I was given a tube of air at the bottom of the ocean.
Slight movements of my jaw would cause leaks, so I learned not to move my jaw at all, which prevented me from moistening my mouth during sleep. I started to get dry mouth. This continued even after changing mask types, since I had learned that behavior. Thankfully it subsided with time. Dry mouth is not a good thing.
I went to the provider and they let me test some other masks. Two nasal masks seemed to be great. One was the Philips respironics Easylife. It seals to my face with very little pressure. There is just a light touch right around my nose.
My perception is that the headgear just really needs to keep the mask in position, so it is something that is just in front of may face, rather than something clamped to it. Something that is comfortably in front of me, and something that is necessary for my survival.
For me, any solution has to work when I am on my side, because nothing has acceptably worked for me when I am on my back. My air passage closes even before I go to sleep if I am on my back.
Try the philips easylife if you can. They have a card to put in front of your nose to get the size. It even works for me with a very full mustache. It helps me to have a gel memory foam pillow that I fold over to the correct thickness to support my head, since i am always on my side. They have some nice ones at one of the wholesale stores at 2 for $10.
Try some other nasal masks at your provider. They should do that for you. That is what they are there for.
Think of it as something you are nuzzling up to for your comfort and survival, like a kitten nuzzling up to its mommy, or a diver to an air supply line, because that is what it is.
The gel portion of the mask does need to be replaced every three months or so. I start to have to tighten the mask up around this time. They are pretty cheap from a number of sources.