What is the biggest sin that God never forgives?

I have acted as a child molester, there was a girl on internet, my friend's friend, and she was talking as if shes an adult, i really took her for an adult, and while we were talking, Demon entered me, and she asked, me that she want to experience with me, and want me to show her on my web cam, i never did that before, but i really did that, on cam, she said to show more, and i did. then she said, she would like to show me her ual part, but she said, shes too shy, and said she has to sleep, i said okay, fine. Then i felt guilty that i must not talk like that, and the vary morning, my friend said, her friend email her about what we talked about, and shes a 13 year old girl, and she has found her online and have known her for 3 days, and that little girl is very upset and tried suicide and i have forced her to do all that and i am Child molester, and i have ruined her life totally, i thought of killing my self as well, but i thought i may investigate first, if she was really a young girl or just pretending, because she was talking about Global crisis and stuff that a 13 year old would never know.