Believe me Chris I have had more set-tos with my doctor than anyone else over the last 2 years. This diagnosis of sleep apnea. Where did it come from and how sure are you that this is not just a symptom of something else? You mentioned heart problems recently and now you mention also problems with speech, which you say are caused by tiredness. I ask again: what other symptoms do you have? Just think carefully back a while. Is there anything else which has changed for you over the past year or so? Anything that happened that might throw light on this situation?
Your tiredness: how does it manifest itself? Is it a kind of zombylike half-awakeness? Do you doze off during the day? When you wake suddenly during the night do you feel distressed or anxious? What is your pulse rate moments after you wake up and do you get any heart arhythmia moments after waking up? Also do you check your body temperature? What is it normally? Also how long does it take you to fall back to sleep after each disturbance? What is your present body weight?
Let me know how you get on with the sleeping tablets. For me the night I tried them was a night of sheer hell. I never tried it again. recently I also tried melatonin but these also made things worse.