Wow, if those truely are, your farthers words, he has to be the least religious person Ive ever heard of. (not sarcasme)
If I got that from my farther??? Id reply to it, are you going to reply?
this is how i would reply

Dear dad, I thank god I contacted you, It was my belief that sombody In my family was In dire need of support, I have however realised that this was gods will, Asumming I needed the help, I contacted you, who I though a reliable source of strength.
However, after taking time to read your letter I have realised that, the person needing help is also too influenced by the words of humanity. throughout the ages people of all types have come to realise how they once thought was wroge, this the bible also teaches us.
Im sorry gods lessons are lost on specific peoples in this world, But Ill do my best to show the truth to everybody I meet, Thank you so much for showing my the truth dad. As from this point on, I understand somtimes there are people who just dont want to listen and/or refuse to admit they have it wrong.
Thank you for helping me to understand I was wrong about you, But as you wish I will no longer contact you from this point on, your are in the hands of like minded people farther, when you find god you will think different, but untill then I bid you and your flat world goodbye.