I'm glad to see you haven't chosen option #1. Sadly though, you've gone with option #2 instead of the far more mature #3. This is the ultimate pitfall of religion-- if you believe that your faith is the ultimate truth, then accepting #3 is impossible. After all, why would you need any alternative moral frameworks outside of The Revealed Word Of God? Say what you will about the pitfalls of atheism, but I know of no atheists who say that atheism is all it takes for someone to understand moral truth. You, on the other hand, have asserted many times on this site that your moral analysis begins and ends with the edicts of your faith. That is a stunted and ultimately unsustainable moral framework. You can continue with denial (#2), or your moral framework will inevitably collapse into either #1 or #3.
An immature person chooses denial. A mature person looks at the world and says "Perhaps given the fact that this ideology in practice sanctions (or at the very least tolerates) the subjugation of women, brutal killings of apostates, heinous acts of violence, wife-beating, the murder of homosexuals, abhorrent forms of criminal punishment, and laws prohibiting free speech, it is not the only moral framework necessary for one to live a decent life." I will leave it to you to decide.
Most of what you've said here is definitely incorrect. First, let's start with gaining morality from a God.
Here's how a God will grant objective morality:
P1) God is omniscient.
P2) If God is oniscient, then if God believes that p, then p.
P3) If God believes that murder is wrong/we ought not murder, then murder is wrong.
P4) God believes that murder is wrong.
C) Therefore, murder is wrong/we ought not murder.
The most decent life you can live is one in accordance with the granted morals of a God.
You can properly derive objective morality from a God. However, on your worldview, you
cannot.You can talk of all those murders and atrocities, but none of them are wrong on your view.
Here's a quote from a secular moral philospher:
"In every system of morality, which I have hitherto met with, I have always remarked, that the author proceeds for some time in the ordinary way of reasoning, and establishes the being of a God, or makes observations concerning human affairs; when of a sudden I am surprised to find, that instead of the usual copulations of propositions, is, and is not, I meet with no proposition that is not connected with an ought, or an ought not. This change is imperceptible; but is, however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation, it's necessary that it should be observed and explained; and at the same time that a reason should be given, for what seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it. "
The core of moral reasoning, obligations/oughts/shoulds, is unattainable by reason. You have not demonstrated how you would derive the idea that something is moral or immoral from describing a state of the world.
If you believe that morality can be objective on a secular view, this is your burden:
"According to the principles of those who maintain an abstract rational difference betwixt moral good and evil, and a natural fitness and unfitness of things, it is not only supposed, that these relations, being eternal and immutable, are the same, when considered by every rational creature, but their effects are also supposed to be necessarily the same; and it is concluded they have no less, or rather a greater, influence in directing the will of the deity, than in governing the rational and virtuous of our own species. These two particulars are evidently distinct. It is one thing to know virtue, and another to conform the will to it. In order, therefore, to prove, that the measures of right and wrong are eternal laws, obligatory on every rational mind, it is not sufficient to shew the relations upon which they are founded: We must also point out the connexion betwixt the relation and the will; and must prove that this connexion is so necessary, that in every well-disposed mind, it must take place and have its influence; though the difference betwixt these minds be in other respects immense and infinite. Now besides what I have already proved, that even in human nature no relation can ever alone produce any action: besides this, I say, it has been shewn, in treating of the understanding, that there is no connexion of cause and effect, such as this is supposed to be, which is discoverable otherwise than by experience, and of which we can pretend to have any security by the simple consideration of the objects. All beings in the universe, considered in themselves, appear entirely loose and independent of each other. It is only by experience we learn their influence and connexion; and this influence we ought never to extend beyond experience."
First, a perfectly rational entity just refers to an entity whose beliefs about what is the case matches up to what is the case. Such an entity would be omniscient (like God); that is, no deductive, inductive, empricial, or any other epistemic error would be made by such an entity.
To demonstrate that moral good and evil are stance-independence/objective & understood by reason rather than by sentiment, you must demonstrate that any perfectly rational being will be causally compelled to act in a particular manner. The connection between a particular line of reasoning (knowing what is the case) and its causal influence on the will of an agent (what ought to be the case) must then be demonstrated as universal to all rational beings to confirm moral realism, no matter how much their preferences differ. David Hume above argued that simply knowing what is the case could not compel a person to act, so he recognized the is-ought gap.
Under your view, which is secularism, there is no way to derive moral claims. There is no way to prove that murder is wrong. At most, you can say "I dislike murder". Stop pretending that your preferences are objectively correct without needing a proof, and demonstrate to me that you can hold any moral positions under your worldview.