When I lost a wallet pass phrase a year ago, I see to it to keep all of my pass phrase under one notebook. Of course I keep it safe as no one knows that I am into cryptocurrency. it's just too bad that as far as I know there is no way to retrieve an account when you don't have the pass phrase.
You are doing well its good to keep your key safe and not to share with anyone as there are so many clever hackers and they can take all your income and your saving away. It's much better to keep it in your account and your PC so no one would be able to know it and take your profit. The private key is something really important that we should not share it with people.