Oh Ouch,

Your subconcious made you tell her. You really don't want to commit suicide. You want HELP. And, you are hoping and so am I, that now that your Mom knows your thoughts, she will get you that help.
Trust me, it wasn't a mistake that you told her. It's the best thing you could have done. I hope that she will get you someone to talk to about your problems.
Also, maybe now, she will try and talk to you more about what you are feeling and why.
I wish you all the best.
Take care,
Linda