I have had very similar thoughts, but I realize that such thoughts are based on our perception of time. There is no requirement for a "beginning" per se. WE require a beginning, because that is all we experience. The Fundamental may not have any concept of time at all. We have such a limited scope of measurements on which we base our theories; less than a century of really good measurements, two at best, all taken from a tiny spec of a world. Our original concept of the physical has been completely destroyed by those measurements (though the concept of "physical" still persists in our rhetoric, but that's a different discussion). Our concept of time and causality itself is very questionable and again, comes from such a limited scope of measurements.

Even the idea of the Big Bang has had to change over, and over, and over again. A new miracle applied to make the measurements make sense (Inflation, Dark Energy, Dark Matter). All these miracles are just shoved in, with absolutely no evidential support whatsoever, except that it is the only way to make the previous model fit the new measurements. Our universe (as we understand the term) may very well have always existed. We really have no idea. I think it is highly likely that SOMETHING has always existed (i.e. Source has no beginning), but there is no necessity for even some small part (manifestation of Source, aka our universe) to have had a beginning either (i.e. there is no real need for a "Big Bang" except we stubbornly hold on to our models, even though those models have serious issues).

In the larger scope of understanding, there may be no need for beginnings or dualities or anything like that. In fact, such ideas may hinder us. The concept of the duality does seem to have some merit, but I think it may very well be only a matter of perspective, and like our concept of "physical," an illusion within the scope of the Fundamental. Merely a manifestation of Source, within our limited perception, as it plays out in the illusion of time, rather than a property of the Fundamental itself.

In other words, all things are a matter of perspective. The Truth is Whatever It Is, and it may manifest, in our sphere of perception, in a myriad of ways (some known, some unknown). Some of those ways give us the perception of space, time, or the physical, some of those ways may describe the Spiritual. I suggest that a more honest approach to physics may show a Unification of the "Duality" of physical and spiritual, showing its separation to be nothing but an illusion. The same may prove itself in our perception of "past" and "future", and all other dualities, if we just take a closer, more honest look.