I don't think his response was for anyone else. It was for you and yes, they do use the term "cool" for many responses, i.e., just like teenagers. I can still remember my xh using the word "cool" for everything and I thought to myself, is there not another word in his vocabulary that he could be using besides the word "cool".
Life continues to move forward and as I always point out...knowledge is power. Continue moving forward.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
