I'm contemplating ending everything
What has made you want to end your life?
Someone I knew a long time ago destroyed my life.
If you are thinking about ending your own life, you are experiencing a mental health crisis and should reach out and receive professional help. Committing suicide is not the answer, as it will devastate everyone who cares about and loves you. Getting help in therapy will help you to process what that person did to you and allow you to move on and live a regular life again.
Don't talk to me like that. It's none of your business anyway.
You're right that whatever caused you to feel this way is not something that I need to know about, but it is my job to help people who need it.  I have to strongly urge you to talk to a therapist or a crisis line before you act on these feelings.  You'll see that you are able to move past this disruption in your life.