I'm sorry this is stressful for you it's like being in a rock in a hard place unbearable to live and seemingly unbearable to die. The way I look at it if this is the route you choose because dying is not easy whatsoever and there is always going to be a chance of something going wrong if you are frantic. Is to pick a option that is
1) at least bearable to you pain wise physically
2) convenient to you as in accessible and realistic for you (have the funds to support this endeavor, have the sources to get this endeavor or the location, and it aligns with your values (family, how you want to be found, what you want to be done with your body after ect)
3) make sure that whatever you chosen you have looked through it meticulously and considered all scenarios (this can be stressful yes I know nobody said it was a easy process) meaning the fatality of your method, if you can actually execute it in a timely manner to ensure success, are there an chances of survival and what occurs if I do survive. If this is really something you want to do cbt is not something you want to survive it could make your situation worse so really think these repercussions over as it will ensure an increase in a desirable outcome.
4) Lastly be realistic and evaluate your goals if you want a peaceful death with abosolutly no pain you are going to have to put in the time and resources to ensure that happens for you. If you just want to die and care about choosing the most minimal way that is grueling on your mind or physical then search for methods and ways surrounding that and do proper research I can't stress this enough.
It truly is sad to see you going through so much internal pain to where you have to consider these options and I hope this was at least a tad bit helpful in guiding your decision to whatever you may choose rather that be death or life. I hope you find peace soon with your decision best wishes beautiful soul
