Hi Lorene,
I know how frustrating therapy can be for someone who is just starting... please remember, though, the first step is being diagnosed - at least you've gotten him that far! How long has he had his CPAP machine? What is his CPAP pressure? How long each night is he keeping it on? Even if he gradually ramps up his time on CPAP (first week - 2 hours a night, second week - 4 hours a night), it is better that not using it all.
There a few factors that might be making therapy tougher for your husband. 1) Make sure he a has a good quality, comfortable mask - Mask comfort is the most important part of therapy! 2) Have him place the CPAP machine on the floor or on a stool beside the bed - it will lower the noise level that he hears. 3) Remind him of all of the side effects of obstructive sleep apnea and medical conditions that can develop if it is left untreated. 4) Encourage him to try the machine for at least one month, and after that time period have him re-evaluate how he feels on a day to day basis (more refreshed, alert, less moody, etc?).
CPAP is very rarely an easy therapy to get used to, but it is a LIFE-SAVING device that changes the lives of many people every day. The best thing you can do is encourage him and advocate for his as a patient - things you are definitely doing by coming to this forum and asking for help!
Good luck and please let us know any other questions you have!