The following is a link to a sleep doctor: http://www.theinsomniablog.com/   My doctor has told me that sleep apnea or a sleep disorder can cause a lot of the problems I am having:  exhaustion, depression, memory loss, inabilty to focus, etc.  He wants me to have a sleep study.  I do know I snore, it wakes me up, lol.  I was not going to go and have the study until I happened to catch this show on a PBS station.  It is currently running on PBS so check your stations. 
I will be going to have the study done tomorrow night (12/10/07) and will update and let you know how I feel afterwards.  While researching the doctor, I ran across a video when he was on the [u]View[/u].  Rosie O'Donnell had the study done and it was found she woke up over 100 times during the night.  She was given a CPAP (a device that forces air through the nose and prevents snoring and the apnea).  She stated she could not believe the difference in how she felt--over 100% improvement in just one day!
Lack of sleep causes so many medical conditions and a sleep study is worth checking out.  Most insurance companies pay for 100% of the study.  If you do not have insurance and your marriage is on the line, it would be worth the money spent to pay out of pocket. 
My son (age 33) is also very depressed and as I was watching this show, I heard him snoring through the walls.  If this study reports that I have sleep apnea and the CPAP works for me, I am going to have (make) him go for the study.  Does your husband snore?  Check out the site I gave you and here are two videos of Rosie: http://www.youtube.com/watch?v=SM1uOcufihw  and  http://www.youtube.com/watch?v=jZTzrVGSOvw    I hope you check this out and I wish you well with saving your marriage.  Kim