MLC is permeated with depression. You can read RCR articles on it.
http://www.midlifecrisismarriageadvocate.com/mlc_overview_depression.html In a way MLC is more like Bipolar (or cyclothymic disorder, a milder form of Bipolar) than Depression. At least for Replayers because it has two poles, euphoria and depression.
As weird as this may sound or (repeated) exercise and just ONE thing that someone can make themselves do even once week if possible.. to develop a routine will help.
IMHO people in this state need to try to socialize in a safe circle of people they trust if they have some. Maybe listen to someone Else's troubles can give their own some perspective.
Your spot on, In it. Problem is it is almost impossible to have an MLCer socialize with a safe circle of people.
Regarding the meds, some here have MLCers who knew they were depressed, start taking meds, then just set them aside, often cold turkey. To some the anti-depressants were making them more agitated. A thing that seems to corroborate that MLC is more like Bipolar, therefore a mood stabilizer, like Lamotrigine, could be more appropriated.
But each person is a different case so, like In it said, hard to tell. We do not have bllod tests of brain tests of our MLCer to know what they are lacking (or having in excess).
You can read bout Bipolar here:
http://mlcforum.theherosspouse.com/index.php?topic=3872.0 Here about the Biochemestry of MLc and Infidelity:
http://mlcforum.theherosspouse.com/index.php?topic=3669.0 In Resources About MLC you will find articles ranging from depression to divorce and other MLC issues:
http://mlcforum.theherosspouse.com/index.php?topic=2297.0Books discussion thread has several books on Depression and MLC:
http://mlcforum.theherosspouse.com/index.php?topic=100.0 and
http://mlcforum.theherosspouse.com/index.php?topic=1971.0Hope this helps.
Sometimes good things fall apart so better things can fall together. (Marilyn Monroe)