Dear Dwight
While your question is fair, I would respect you more if your conclusion - disavowing God - was reached after extensive study and exploration, rather than making assumptions based on limited knowledge and understanding.
Let me quote from the sacred Zohar - the primary Kabbalistic text that gives us insight into the deeper dimensions of life beyond our superficial understanding.
"All souls that come into this world are born whole, although some may be blemished on the exterior. This is not some kind of punishment for the soul, as some suggest, rather because of a profound love God has toward that particular soul."
God is compared to the moon. Just as the moon waxes and wanes, sometimes its light is more manifest and evident in the world, while at other times far less so. So too God's presence is sometimes more obvious and shines brightly in our world while, at other times, far less so. Some souls emanate from God during those brighter moments. Such souls are born into strong and healthy bodies. Other souls emanate from God during the darkened moments. These souls are born into disabled bodies.
Why would God's presence experience darkened moments in our world? Because, as the expression goes, "The bigger they are, the harder they fall." The highest emanations of God fall to the lowest and most darkened places. When the Talmud makes reference to the idea of the "exiled state of the Divine presence", it refers precisely to this loftier level of the Divine that is expressed in the lowliest levels on earth. It follows that those souls born into disabled bodies emanate from the highest levels of the Divine.
Why must the highest levels of the Divine occupy the lowliest levels on earth? Because the primary purpose of life is to elevate the crass materialism and physicality of our world onto a higher spiritual plateau. The lowlier the material, the higher the spiritual energy required. It is precisely the loftier souls that emanate from God's more darkened moments, i.e. the highest spiritual emanations, that are best equipped to combat the more prevailing darkness in our world.
You might think of this in context of an undercover agent. When a burly soldier steps behind enemy lines, it is obvious why he's there. When a soldier is camouflaged however, he can be so much more effective in ways unimaginable.
The greater souls emanating from the highest sources in the Divine are "conceived" when the Divine is in its darker stages, into weakened or disabled bodies, because such souls grapple with the most challenging parts of our world in ways not readily discernible.
Consider how once disabled people were typically confined to institutions and how society as a whole has now woken up to the reality of how they are human beings as well and can contribute to society in their own unique way. Torah has been advocating this approach since the beginning of time.
Such souls evoke compassion from people and generate a lot of benevolence around them as a result. Many schools today encourage the participation of disabled children which in turn has a dramatic positive effect on many of the other children around. It teaches them compassion, sensitivity and much else besides.
If we’re all foot soldiers in God's army, then such souls as contained within the disabled are, in fact, the elite. Hence, the Lubavitcher Rebbe once said, when addressing a group of disabled soldiers from the Israel Defence Force: "You are referred to as the nichai tzahal - 'disabled war veterans.' This is a mistake, because 'disabled' implies inferior. Really you ought to be called metzuyanai tzahal - 'the distinguished of the military' because clearly, on account of your disabilities, you have unique spiritual qualities and God has selected you to achieve great things in this world."
If the Kohen has a blemish, he is not being 'prohibited' from doing work in the Temple. He is 'exempt' from doing that work because he has a unique soul and for him there is a higher calling.
When Moshiach comes, elements of the Divine permeating the lowliest of places will shine brightest. Those special souls contained within more challenging bodies who will have achieved greater purpose on earth, will shine equally bright.
Maybe it's time for you to rethink God.

Dear Victor
I could start with Maimonides, who says it falls under the Biblical prohibition of: "There shall not be any promiscuous men among the Jewish people; nor shall there be any promiscuous women among the Jewish people." I could refer to Nachmanides, who maintains the prohibition is implicit in the Biblical injunction: "And the earth shall not be filled with immorality."
Most authorities deduce it from the command to marry. This is most telling because inasmuch as "consenting adult" is the modern term for "anything goes" in our laissez faire world. The reality is that a disciplined society is a more successful society. With every desire being expressed at whim, it’s no wonder we have such a high proportion of obesity, drug addiction, alcoholism and so on.
It also explains why we have such high levels of depression, because of the relentless pursuit of illusive satisfaction. True fulfilment is only experienced when the pleasures of life are conducted within the confines of a moral framework.