I've been retired for 16 years, keep busy with lots of stuff including a part time business run out of the house. It's more of a hobby than work, and just enjoy the 3 or 4 hours spent each day doing it.
I'll even work on Saturday a little, and maybe a Sunday afternoon if the weather sucks, but come Mondays my enthusiasm is ZERO !!
Can't be that I"m overworked, or the work load for the week is to large, it's just that I don't really feel like doing anything. Find excuses everywhere to stay out of the office, usually end up just pissing away the day, then comes Tuesdays and everything is fine and work resumes.
I am retired so I guess this problem is no big deal, but it's just that for some reason Mondays SUCK !!!!