I am 48 years old so I’ve been an atheist longer than I was a christian. The journey has been long and only within the last decade or so have I softened my views on religion because people need to be happy and if believing in god is part of that then, so be it. I’m only atheist by the strictest of definitions: I reject and deny the existence of god(s). There’s a subtle difference there between what is belief and what it is said. I don’t say “there is no god” no one can know that. Engaging believers in conversation does far more good than ignoring them or berating them, which is why I am responding to you. My answers and comments to your questions follow:
“I’m very sad to hear you say you have become an atheist.” Why? How would you feel if I said I was sad that you believe in god? I know you mean well, but this is quite offensive to none believers, would you say the same to a buddhist? or a hindu? They don’t believe in god. To them christians are atheists. Which, by the way, did you know that christians were some of the first people to be called atheists by the greeks? atheos means without gods, which is what christians were to them.
“What does that mean for you?” Freedom from fear. The idea that I am born of and with sin is offensive to me and I find it abusive to children. Children are born with a blank slate and teaching them that something is wrong with them without cause or reason does more harm than good.
“What did you believe in before?” I was a christian.
"What changed you?"
It started with doubt and curiosity about definitive statements of truth made by clergy and the bible, I could find no convincing reason to believe most of them. As I got older I continued finding more reasons to not believe. I have studied christology (history of the bible) at university level and that served to further support my beliefs. I recommend to everyone to learn how the canon was written and finally put together. I also recommend to all atheists to read at least one translation of the bible, more if possible.
"How much did it change you?"
I am kinder and gentler to my fellow man. I don’t judge people for who they are, only what they do. When I do judge people I keep it to myself and say “there for my good fortune go I”. I know myself better than anyone should, it is a two bladed sword. I am filled with wonder at the vastness and beauty of life, nature and the universe. I know that good and evil are not a binary proposition, that we live in a spectrum of both. Good people are as capable of great evil and great good. The majority of people want to and do good. The past few years I have been learning a lot about skepticism and how to use it to parse knowledge. Through skepticism I strengthen and weaken the things I believe in.
As you may gather from my initial post, my thinking has evolved to where belief in god is just fine with me. I have a much bigger problem with using faith to deny the reality that science presents. Stephen J. Gould proposed that Science and Religion/Faith are non-overlapping magisteria - the notion that each is concerned with different aspects of the world. Religion concerns itself with the divinity and the soul and science with the natural and physical world. This, to a certain extent, is how I see things.
I hope this satisfies your questions, please do not hesitate to continue this conversation.