Highly recommended!

(Also, I think that The Long Riders was one of Walter Hill's best films.  Also... Even though he was shot up, Cole Younger somehow survived the Northfield shootout. When he passed away at age 72 (!) he apparently still had more than a few bullets embedded in his body from the early days.  Info here. I'd always hoped that David Carradine would star in a sequel to the Long Riders -  even as a short film - portraying the older Cole Younger as he went out on the lecture circuit after he was released from jail.)

"why do people commit suicide naked"

from Wiki Answers

Perhaps they were 'strip ping away' what they felt was societal the clothing being a symbol of what society had to offer them. Also maybe at the same time they are saying society is messed up - not trying to be graphic or harsh but doesn't that imagery in your head give you the same cup of tea so to speak ? Not a pretty scenery in short.

As far as her stripping her children naked and walking into traffic same as before it can be taken in a broadened spectrum or looked at as the obvious answer 'just pure insanity'.

I think the answer isn't as much apart of why as apart of how. How are their minds running. What provoked them to do it.

and if Why; Why are there rare cases of suicidal impulses provoked with nudity and stripping of garments.

But only deeper probing and questions can answer this - perhaps probing in correlation to repetitiveness aka insanity is apart of the answer.

How do you define it though when every one goes to work repeatedly on any given day or you eat 3 - 6 meals (6 being the obvious turning 3 into 6 smaller portion meals).

It has a lot to do with how your brain functions - that is a common sense sort of theory wouldn't you say? Hint; outside factors such as sensory cortex, audible and or neurological disorders in general could accompany and compile with the already depressive suicidal tendencies and dementia.