If you choose to be happy, be present. Regret, failure, disappointment, and fears are rooted in our past. Apprehension and anxiety project on possible future eventualities.
Here and now, fear and anxiety do not exist. You have a choice whether to embrace a happy state or not. There are silver linings no matter the situation; do we choose? Yet to fixate on what has happened on what may or may not occur, to what avail.