Hey, guess what? I, like many other atheists, have indeed been open to God. A while ago, my husband said to me that since his religion was important to him, he wanted me to give it a go as well. So I said that I would be open to God and if God wanted to give me what I needed to be e believer, then I would accept it. So I prayed to God to give me what I needed, and you know what I got? Go on, have a guess.
Now the thing is, I was sincere in wanting to get to know God if he was real. And I got nothing. And yet you assume that I have never even tried because you can't comprehend how someone could do what you did and get a different result. You assume that because I'm an atheist that I haven't been open to God, because you just can't comprehend how I could be open to God and not become a believer.
Well, too bad. I've done what you said, and you - just like lots of other Christians before you - have just assumed that I haven't because you can't understand that people can do it and not get the same results that you did.