I'm so sorry to hear how overwhelming the dark feelings have been for you recently... You say you aren't an imminent risk for suicide, but have simultaneously been taking action to prepare for it. Do those actions provide relief that you're working towards something you feel will make the only difference to your current condition? Suicide means you never have another choice.

If it's the people in your life, you can still write goodbye notes. But you can get in your car or on a train or in a cab or on a plane and leave, and start a new life. You always have another choice. The other choice may appear more difficult than killing yourself - you're already at rock bottom and risking going any deeper may be unfathomable. But if it makes a difference you might just allow yourself that you're biding time. Why not try every single crazy ridiculous idea? You've got nothing to lose. The alternative is so final you might as well.

I've had those closest to me explicitly state they don't love me, don't care about this, and are done with me.

No matter who they were to you in the past, fuck those people. You don't need someone like that in your life - someone completely mentally healthy doesn't need someone like that!

Their love or approval does not define your intrinsic worth as a human being. Your writing demonstrates that you're an intelligent person, you can conceptualise the steps involved in various choices, and you have deep self awareness. These are all the positive traits of you, a good person, and whoever they are they don't deserve for a second to make you feel your life is any less valuable without their consent.

You have been trying, and I'm a total stranger from probably the other side of this planet we call home, but I'm fucking proud of you for being strong enough to continue with all that hanging over your head.