I often have the same lack of motivation and I hate it. Doing even the most simple thing requires pushing myself and when I finally do it the sensation is like gravity has doubled and enormous effort is required. The really galling thing is that I know that most of the time I actually will feel better if I push through but that is rarely enough to convince me to start. What a sad situation: Knowing that something is likely going to help but being unable to summon the strength to start doing it.