How common is rage with sleep apnea?

I am at the end of my rope. My husband has been struggling to get his sleep mask to work for him consistently. Sometimes it works for 2-3 days, but then something happens and he doesn't get a good night's sleep. He troubleshoots it, it works for a while, then something else happens.

He keeps exploding with anger over the smallest things. I'm walking on eggshells because I never know what's going to set him off, and it's always something that is relatively small. Most of what he is saying doesn't make sense when he's trying to explain himself.

I don't know what to do. I keep telling him how I feel, how I'm on edge all the time and I'm scared. We've done couples therapy before so I am hoping he'll be open to that, but he is very resistant to seeing a therapist for himself, which our therapist thought was necessary.

He says therapy doesn't work for him and he has struggled to open up and trust the therapists he's tried. I feel like therapy is necessary to help him figure out how to troubleshoot his CPAP and also address his underlying anger issues and past trauma. I'm just trying to get a sense of how common these issues are, what I should do or if I just need to plan to leave.