Where we differ is that I firmly believe my God is your God, and neither of us could ever change that, no matter how much we may want to.

That sounds like a you problem. If your god expects me to believe that it's real, then it's going to need to move itself to prove it. Your testimony isn't sufficient. I've already been there, done that and bought the t-shirt.

So yes, Christianity does apply to you, even though you don’t want it to.

You're entitled to think that's the case. What you think in the privacy of your own head is your business. The moment you think you have the authority (as too many Christians do) to make me follow it is when we have a problem.

I only want to take every chance I can get to give testimony of my own experiences with God, and to follow the Great Commission for anyone who actually cares to let a seed get planted.

And this is why we can't be friends. We've heard the story. We've heard the testimony. We remain unmoved. At this point, the only way to describe this behavior is harassment.

The world has heard the message. Let it go and leave us alone.

So does that mean we can coexist? I certainly hope so, but I recognize you may think I’m overbearing.

Christians in Europe have been highly successful at coexisting with non-Christians without harassing them. You might look into their example.