Brought up Mormon.
From the time I was 24, to the time I was 31, I was a devout Atheist.
Now I'm Christian.
You want a proof, or you won't believe. I'll make this simple for everyone. You won't believe.
A proof must demonstrate that a statement is always true. What that means is that in all cases when X, then Y
If I do X, then God will always invariably do Y. Also, it has to be reversible. If I want more Y, then all I have to do is X.
The problem is with "I." My will is that Y, therefore I will do X.
God is not a cosmic slot machine. I can't give you an X to do to get Y. Just like someone can't give me an X to do, that will guarantee I get Y from you.
If I you and I were friends (had a relationship), I'd likely know some things about you. Maybe your favorite beer for example. One day I decide I'd like to try one. So I ask you, "hey, can I have one of those?" Your answer could be no. You'd be well within your right to say no. They are after all, your beers (you greedy SOB). On the other hand, you may say yes (see, I knew it, you're actually a nice guy). You may even give me one for the road (wow, an altruist).
The fact of the matter is this, there is nothing that I (or anyone else) can say to you that will MAKE you believe. It wasn't anything anyone said to me that changed my belief system. I could hand you every argument there is about why God. If you were skilled enough you could dismiss them all (and maybe you are, I don't know).
The offer of having a relationship with God can never be more than an offer. Anything else is tantamount to rape (yes, I chose that word carefully). I compare militant Christians, Muslims and Jews, to militant Atheists, in that they try to force you to think the way they do.
So to wrap this up, next time you're in Colorado, look me up and we'll get your favorite beer. And, if you're not a beer drinker, fine, I'll drink yours, cause that's how I roll...
Bob Dylan - "And I stopped in for a beer..."