The friend I said goodbye to, I did actually thank them for what they taught me while we were friends.

Heck sometime in the future, I could probably even thank my xh for the lessons I have learnt as a result of him being in my life. Not saying I could do it now, not even in the next year or so, but maybe if we ever cross paths again sometime in the next few decades, I could possibly thank him (ok I'd never thank him for being emotionally abusive).