A better question is how you used the card you were dealt - i.e. will you be satisfied with what you've done with your life when the end comes.

Because if the answer is no and you feel you have to end it sooner than necessary, you haven't played all your cards yet. If the answer is yes, the end will come all too soon and the question is moot.

but how come we can't go out on our own

You absolutely can. It called 'an heroing'

I mean, you may not have permission, but you have agency.

1. You can. The fact that it's illegal (is it actually illegal? I realise i don't know) won't be a problem once you're gone.
2. There's a whole life inbetween the beginning and the end, they don't really have much to do with if your life has been full or not imo.

It's called the right to death, and some folks very strongly despise the abrogation of that right