I feel like such a hypocrite because I told her suicide wasn't the solution.
All my god damn friends love their lives, which makes me hate the fuckers even more (sometimes), so I can't really relate. I imagine if I were in that situation though I would also be a hypocrite and tell them that there's still hope, despite wanting to end everything for myself.
I have no idea what is happening in your life but based off of the information you gave I would personally attempt to obtain a different method independently to save anyone from the blame and then simultaneously while you work on that attempt to dissuade your friend from committing suicide at all costs. Then in 3 months to 1 year you can re-evaluate and determine whether to die or to postpone the decision for another few months.
I know, I know I'm a terrible person (and I don't mean that sarcastically), but if we look at this from an excruciatingly cynical point of view, if your friend really needs to commit suicide they will take your advice and the advice of many other people and then decide for themselves. What you say can have an impact but ultimately they will be making the decision on whether or not to do it themselves, and despite what people will say, no one can really stop them once they determine what they want. I imagine, if they did end up deciding to die, their final days would be even more terrible if they reached out and no one really seemed interested in responding to their plea for emotional support. Of course I wouldn't know, you won't catch me asking my friends for emotional support fuck that.
Considering that you will soon die I would also ditch literally all obligations and save just barely enough to go see the UK. They talk with the funniest sounding accent I've ever heard in my (relatively short) life but I've never gotten to hear it in real life. I can't just let it end like that without getting to be surrounded by these strange freedom hating people, and honestly I don't think you can either. You could also go to Ireland if you had some relatives who came over 100 years ago like me but they're almost the exact same so it'll be a decision you'll have to make on a whim once you get there. I'll leave that part up to your better judgement once you're there.
Here is that list again of exactly what would do, but in a more concise and ordered format (annotated and dated for your convenience):
1 - 10/5/23 - 12/31/23 ) Convince friend to not die and/or give some bs about how there's a place for them in the world and/or find god (bonus points if you try to convert them to scientology please send pics)
2 - 1/1/24 - 5/1/24) Ditch all current obligations, begin saving for trip to UK (consider custom ordering "UK the 51st State?" memorabilia beforehand to wear while you are there, again, please send pictures of you with the native British population)
3 - 5/2/24 - 6/30/24) Go to the UK, film the british people and their distinctly hilarious accents. Extend your trip by staying in hostels or by working gig jobs with under the table payment (in theory you could try to overstay your visa indefinitely, but england is a dangerous place so I wouldn't)
4 - 7/1/24 - 10/1/24) Secure suicide method independent of your sister. Something tells me your method may not be reliable either if it was something some normal person had lying around. I, personally, would not settle for anything lower than a %85-95 percent success rate. If you are going to do it make it painless and ensure that you won't end up in a vegetative state. The extra time spent preparing is nothing compared to the amount of time you will be trapped in your own body unable to move if you screw up.
5 - 10/2/24 - 10/5/24) Re-evaluate and determine whether to end it or temporarily extend it.
I realize now that this sounds like some pro-life propaganda over here and honestly that's just not my intention. Ultimately whatever you do is in your hands and not mine. I'm on here because I want to die as well. If you ask me what I would do in this situation though, it would be to simultaneously get affairs in order so that someone isn't blaming themselves for what happened and also cutting out unnecessary burdens or obligations and partying like its 1999. I'll admit I've never actually been completely free of obligations and I doubt you have either, but I would at least try freeing yourself just once before you make your decision, since it sounds like (based off of your post) that you'll probably end up waiting sometime anyways if you've already waited 6 years and are telling your friend not to do it.
Regardless, I am just a stranger on the internet who you will likely never meet. I can only tell you my honest opinion, with some dumb sarcasm thrown in (sorry its getting late). Nothing that I type here has any real substance or meaning. I won't disrespect you by attempting to give fake platitudes, and I won't pretend to be so great that I could know what it feels like to be in your shoes.
Carefully analyze every option and then make the right decisions for you and only you. One decision at a time. If you're as dumb as me I'll see you in the UK.