Personally, i don't understand why it's classified as "blaming" simply because it's labelled as "selfish".
we can go over the semantics of it, but at the end of the day, it's who benefits from the action that classifies it as "selfish" or "inconsiderate". In a CTB scenario, even if the attempt is unsuccessful (meaning the person survives) carrying out the attempt itself (i.e.: jumping in front of the train) benefits only one person: the one attempting. The fact that it succeeds or fails is an entirely different thing.
Yes, we have different circumstances, and no one is in a position to tell someone or the other why their misery is not enough to warrant a CTB attempt or not.
Trauma suffered via the act of watching someone suffering before the end and trauma suffered from seeing a dead body isn't really in the same league, so it wouldn't be accurate to lump them together and say that the amount of trauma is just the same.
TL:DR; I agree with @UKscotty , @lita-lassi