If you need a day off- whether your car won’t start, you have an urgent family emergency or you need a mental health day- DO NOT EVER tell your employer why you need it. Most of the time they don’t want to know! I assure you, (and this may sound harsh) your attempt to pepper-in sympathy does not go as far as you think in the backend. Please stop trying to engineer a request you think they want to hear!
Request the day and YOU ARE DONE. You filled your end of the request!
Your employer and especially your boss are not your friend, HR is protecting the company not you, and it is not legal to be forced to disclose why you need that day (especially if it is medical related).
Request the day, delete the reason why you need it off if you typed it and consider quitting if you are being forced to provide justification. “Eat shit and die, I need the day, asshole” is the justification, you don’t need to tell them that!