Of the arguments you think I'm afraid of:
1. A person sacrificing their life for others is not mentally ill (assuming the sacrifice directly achieves the goal - i.e. taking a bullet for someone). It's an action which proves how much they value the lives of others. ...which has nothing to do with your suicide.
2. No species has evolved immortality because the goal of evolution is for each organism to live long enough to pass its genetic material to another generation. ...which has nothing to do with your suicide.
You gotta understand, I'm not trying to win an argument with you! If that was all I wanted, I'd wait 10 years and win by attrition.
Your brain is ill, and this then caused you to sever social connections and become suicidal. I am telling you to seek medical advice from medical professionals.
You claim to be operating just fine, so how about you go verify it in person with a doctor? Tell them what you told me, and see which of us they agree with?
If you don't, then we know which of us is "afraid".