I know how deeply you struggle with the desire to have peace and that death looks like that peace to you. I won't argue you on that one as that is not what this thread is about. I will just address whether or not it would help or hurt your mom to know what is going on inside you. It will definitely help her. Communication--especially of the deepest and hardest internal struggles--is all we humans can really ever offer each other. To be your authentic self with your parents takes real courage. It is the same for parents--to step out of the role and simply be your authentic self to your adult child is probably the best road into a good adult relationship. So yes, a resounding yes, I think it will do more good than harm.
Although I do not believe that my son consciously overdosed the night he did, I know that death also looked like an answer to him on many many dark and hopeless days. If we had not talked so honestly about death, his views of it, my views, etc. I think I would have less peace than I do now. One of the things that he said to me on so many occasions was" I know I have a beautiful soul and it has a home. I don't think it is here, though." At the time, I used to argue with him and if he were here today I would argue it still. I believe that he had not experienced the world enough outside of school, his hometown, a very small slice of the big miracle that is out there when you come right down to it. But at the same time, one of the most terrible things a mother can suffer is to see the child that she sees as such perfection, such a miracle, loathe himself or see himself in a negative light. So my son's words, his description of his soul as beautiful, are words that I hang onto when I get overwhelmed by remembering his despair. I can be comforted by the knowledge that he did in fact share my view that he was a miracle, that his essence was perfect. I have no beliefs about what a soul is. I only know that each of us carries a very pure essence within. We start losing it the moment we take our first breath outside of our mothers bodies. We cover it because with useless distractions according to the place and times we are born into but it remains accessible when you go deep enough inside.
I love that you titled this thread courage. I think a lot about courage. People tell me every day how courageous I am for surviving my son's death. That may be true but the courage that my son had outstripped mine by far. He dealt with crushing depression and suffocating anxiety that he could neither understand nor fight off so much of his short life. The fact that he could also feel such immense joy and beauty just made it all the more devastating when he could not feel that. I think that your mother should hear you talk about the courage that you have every day dealing with the feelings that you deal with. I know that like me, she is probably very proud of you in ways that you cannot imagine.
i hope that you will never take your life. I believe so strongly that there is a way to embrace the emptiness and that by doing so you transform it--that this is accessible to every one of us but some of us have to struggle so much harder to get there. The paradox is that those for whom the struggle is hardest gain the most from the battle and have the most to teach.
I hate using fear or guilt to try to talk someone out of the wish to die but I cannot even begin to explain to you all that is contained in my reality now. Losing a child to their own despair is an added layer to the pain of losing a child. I write and talk to every mother that I can that comes through Bluelight after losing a child. The guilt for us is a lifelong reality. There is no way to leave it no matter how well your rational brain works at it.
When you talk to your mother you could frame the conversation in the desire that you have to let her know you more fully. That is a gift to both of you. Trying to protect someone else from worry usually does just the opposite.