When related to personal questions is "I don't know" only a euphemisms for "I never bothered to think abou it"?

Sometimes "I don't know" is a perfectly reasonable answer. It could be otherwise expressed as "It seemed like the thing to do" or "I didn't think there was any harm"

As for why are you angry (sad, irritable, happy) it's the one that is actually most understandable. Sometimes we don't know why. PMS does it to most of us females, and men have their inexplicable moods too. Even small children and animals can get in moods.

May 13/17
9:50 pm
EDT

I don't know

Is a 'I'm not brave enough to tell you'

"I didn't value how I made you feel over X" is a level of vulnerability few bother reaching for. Spending time with people who seek truth is key.

I don't know is just another way of saying *it seemed like a good idea at the time.*

Apr 25/17
1:37 pm
EDT

It could also be "I know exactly why but don't want to tell you"...

And no one showed us to the land
And no one knows the wheres or whys
But something stirs and something tries
And starts to climb towards the light