It's a toxic line, that is designed to manipulate you into sacrificing yourself for the sake of others. I really wish it could die.
That said it is something that I consider. And despite the fact that my father is one of my abusers (and through recent conversations he's finally starting to come to terms with what he did to me and how it has impacted my life) I will not ctb before he passes. He lost my mother this year after 55 years of marriage, he's hanging on by a thread because his personal religious beliefs say that if he gives up and ctb he won't get to be with my mom after he dies. If I choose to ctb before he passes it will crush him and may cause him to violate his own belief system. I will not do that to him, not even out of spite or revenge. Does he deserve that consideration? Hell no. But I won't compromise who I am, knowing it would punish him.
As to the rest, siblings I've talked to and they know where I'm at. They will be undoubtedly sad when my time comes but we've never been extremely close (I am 10 years younger than my closest sibling, and the rest are even older than that) and they've been prepared for the eventuality. The real friends I have all know where I'm at and know there's nothing they can do that would or will change my mind. It will certainly impact them, to some degree or another, but I don't believe it will be a trauma for them. My wife... I don't even know. We are at best roommates at this point, but roommates with a weird interdependence. She knows where I'm at but is in denial. She brushes off things I say and do, and refuses to engage with me on any attempts towards recovery. She seems to think if she ignores it, maybe it will go away. Honestly, I think she's more scared of being alone than she is of losing me. She has her own demons to fight too and while I'm sad that she will undoubtedly be hurt, I don't know what more I can do to mitigate the damage short of making sure she's not the one who finds me.
So, do I think of what it will do to others? Absolutely. Is ctb ultimately a selfish act? I think in the end it has to be. And that's ok. Ultimately we are responsible to ourselves first and foremost. And the only person who can decide if ctb is best for ourselves is ourselves. I don't think it's a decision to be made lightly, a decision to be made impulsively, or a decision to be made without exhausting every avenue to be able to recover. But it is a decision to be made for ourselves, and at the end of the day I respect each person's right to make that decision.