"Simple answer: this is a logically contradictory question to ask. It's basically the same as saying: someone baked this piece of bread, then, who baked the baker?"
The baker evolved through mutation and natural selection. You envoke an answer outside the provable realm. By doing that you release all bounds. There is no limit to what you can place in that realm.
"The universe did not always exist, and provably so."
Then you are not agreeing with the best of our combined knowledge in knowing for a fact what happened at the very start of the Big Bang? I though we were uncertain up until 10^-38 seconds or so. Did the Big Bang occur in this universe or did it form the Universe? I don't know. Does anyone at this point? Is there any outcome that you would consider an argument against a god? I would not accept the prove of the universe not always existing as proof FOR a god anyway.
"The very fact that we're having this discussion is proof that God, The Creator, exists."
When I look at our DNA, and compare it to every other organism on earth, I see a tree of life, dependencies, common ancestors between species. No proof that a creator exists. I any case, simply stating that anything is proof a creator exist is a bit simplistic right?
"God has sent us many messengers, and provably so."
Could you point me to this proof? Is it a reproducible experiment? Can I do said experiment at home and come to appreciate your point of view?
Could you suggest any experiment that could help me accept that there is a god?