I recommend calming down and coming to a sound minded decision. Ask yourself is ctb what you truly want or is it an easy way out to escape your problems. I don't mean this in an offensive way either it's a serious question. It's your life and your decision. I will be here for you and anyone else who needs me here. If it really comes down to ctb I do have a suggestion that won't traumatize anyone else.
You could try making chloramine (ammonia+bleach). This is really important so pay attention. You must have a small enclosed space with little to no ventilation. If not you will likely end up in a coma with severe brain damage. If done right you will pass out in ~1-2 minutes and die in around ~10-30 minutes.
I really think ctb should be an absolute last resort. If all else fails. However like I said before it doesn't matter what I think it's YOUR life and YOUR decision. Just make sure your decision is a sound minded one.
I hope only the best for you.
I hope you feel better soon.
Stay safe