Why, in theory, do you think we are here on Earth?

I used to believe that we came from monkeys and that we are just useless parasites feeding onto the planet, I felt that we were worthless to this whole world and that it would be better without us, I felt as if I had no purpose it led me to deep deep confusion about life and it led me into a dark whirlwind of depression, you know that feeling when you feel disconnected from everyone you feel as in your life is this boring pathetic useless existence, if not that’s just how I felt till one day someone gave me a bible as a gift I felt as if they were trying to make me a believer since they were really enthusiastic and I didn’t understand how someone could have so much faith over something that
I believe didn’t exist until one day I was led to the “edge” I looked in the mirror and told myself I’m useless with no purpose I was abused by a someone related to me in a very inappropriate disgusting way I couldn’t forgot that chilling touch that made me feel filthy I never felt the need to open that bible until that moment I remembered how enthusiastic the person was all I wanted was what they had that real happiness that fulfillment they had so I opened it and from there I found my purpose I was able to get over all my traumas and I began to do the same thing that one person did to me, preach to my friends to strangers and to anyone who would be willing to hear, I now believe I have a purpose to spread the gospel and help people who felt similar things that I did, let me just say I don’t know who you are I don’t know your story but I do know it was no coincidence I ended answering this question.

I believe we are all here for no reason, no life truly matters there is no god, we just exist and it’s been like that forever