Dear Mr. Ritz,

good to hear that your wife has found another, more gratifying job, and that you are now better off financially!

My wife has been having mental issues. Lack of concentration, forgetfulness, brain fog etc…

Do these issues affect her ability to work? It’s good she’ll be seeing a doctor about it…

I’m pretty sure my attacks were due to concern for family and friends.
What I find strange is I didn’t have the feeling of fear, dread or other feelings you’d normally have when I heard the news.

It could be something below your conscious awareness, but still getting triggered. I don’t know how else to calm yourself down (beside various relaxation techniques, which you’ve been already doing), except by looking deeper into the problem and see what it is, i.e. what you are afraid of.