I read “not existing” as “not ever existing”, so the difference is everything that happened between when you would have started existing and when you would have committed suicide.
(English badly needs separate words for ‘physically exist at a particular time’ and ‘exist, in an abstract timeless sense’. Lots of philosophical discussion such as A-theory vs B-theory would then be shown to be meaningless: does the past exist? Taboo “exist”: the past no longer exists_1, but it exists_2 nevertheless.)
I read “not existing” as “not ever existing”, so the difference is everything that happened between when you would have started existing and when you would have committed suicide.
(English badly needs separate words for ‘physically exist at a particular time’ and ‘exist, in an abstract timeless sense’. Lots of philosophical discussion such as A-theory vs B-theory would then be shown to be meaningless: does the past exist? Taboo “exist”: the past no longer exists_1, but it exists_2 nevertheless.)