First and foremost, I am sorry to hear it has come to that. But as much as it saddens me to hear about your suffering, I am glad this forum has helped you to find peace, both on your life, and that it has helped you find a way to reach eternal peace afterwards.
As others have mentioned, we will support you on your decision, whichever it may be, both if you decide to stay with us, or to leave for a better place. Life can indeed be harsh many times, but knowing that the peace of the afterlife awaits us, there is no point in rushing it, and negating us to enjoy the little things of this existence. That being said, I do understand if you feel like you can't endure it no more, or that there is nothing left to enjoy for you on this life, on which case, as stated before, I equally support you on your decision.
I am glad you could get some SN. I have two kilos myself on a drawer. An overkill, I know, I just didn't know how much was necessary until way after I had made my purchase. It is a good method, as many have commented here, well documented both from official sources and testimonies of either people who regretted it at the last second, called for medical help, and were saved, or of people who saw a fellow member die and accompanied them until their last seconds.
Make sure to do a proper review of the resource section of this page, if possible to get all the secondary medication you could source, none is necessary but it makes a more pleasant experience, and of fasting.
All of this being said, and re-assuring you that I support you on your decision, I want to nonetheless make sure that you fully understand the decision you are making. If you wanna talk about it, what you are about to do, your reasons, or your life, feel free to do so.
We love you, and support you. Best of luck my friend. You'll find the peace you deserve.