Assuming this isn’t just a shitpost:

Yes, calling someone a useless piece of shit when they are trying hard, but failing, at doing something very difficult makes you an asshole. It is the opposite of constructive feedback; it’s just an insult. In case it hadn’t dawned on you, the guy wasn’t just having to solo parent, he was having to solo parent while presumably worried sick about his hospitalized spouse.

Do I blame you for being frustrated and snapping? No, but it doesn’t mean you weren’t a huge asshole in the moment. Own your mistake and apologize if you have the introspective wherewithal and didn’t just make this post seeking validation.