I have no idea how everything came to be. It's too immense for me to even fathom, but I agree. The universe, in all likelihood, is endless, with only energy being constant. I believe Stephen Hawking proposed that it might be seen as a single sided, three dimensional surface with no beginning or end, much like a sphere.

It's a better explanation than a great, complex entity that always existed yet had no creator itself. It's best to start simple.