“If shitty things happen to you, then you will not like that and it will suck,” still doesn’t break the continuity of self. Fundamentally that same exact thing can happen to the current flesh and blood you and it would be horrible and destructive: you can be disfigured through an accident or through someone’s cruelty, you can be locked in a cage and dehumanized on the whim of the state-sanctioned professional violence men and given a farce of a trial by the dysfunctional shitshow that is the legal system, etc, but no one is going to argue that shitty things happening to you ontologically unpersons you in some sort of mystical fashion.

You can be reduced, you can be transformed, but you continue existing for as long as vital functions do. Talk about someone becoming someone else, or dying in truth long before they died in body, those are just poetic attempts at articulating sorrow and loss.