I must respectfully disagree with Keyes here. Sex plays an important role beyond the conception of children: it strengthens unions. Humans have much more sex than is required for reproduction. Unlike other species, human sexuality is not connected to ovulation; human females desire sexual relationships even when these relationships are unlikely to result in conception. (This fact of course is exploited by observant Roman Catholics who wish to enjoy sexual relations without pregnancy resulting; it is referred to as the rhythm method.)
As regards to homosexuality: The rampant promiscuity, drug abuse and disease of the gay community is alarming and tremendously sad. I pray for the several gay men I know who engage in these dangerous behaviors. But I am no longer prepared to condemn my close gay friends and family who are in loving, monogamous, long-term relationships. I admit that this is difficult to reconcile with my Christian faith.
Well everyone is entitled to make up their own idea of what a marriage is, aren't they? Where do we start and where do we stop?
By revelation we know: God made us male and female for the purposes of partnership and procreation. Sex is accomplishes both in a marriage.
Dr, Keyes quotes the Genesis revelation; "The two become one flesh" and on that basis a marriage can only occur between a man and a woman as they come together for partnership and create offspring [one flesh]. Using sex to promote a partnership outside of marriage is not what God intended. Sex is by God's definition, marital intimacy, not a tool for "strengthening unions".
That understanding, while quite common these days, is outside of the Judeo-Christian revelation [pagan].
Dr. J. Budziszewski (What We Can't Not Know, Revenge of Conscience, Written on the Heart http://www.amazon.com/exec/obidos/tg/detail/-/1890626546/qid=1094449575/sr=8-1/ref=pd_ka_1/104-6823304-2215946?v=glance&s=books&n=507846)
makes the analogy that if sexuality were breathing, one would have the air way, another would have the lungs with the gas exchange mechanism.
I think Dr. Keyes is right, as is Dr. Budziszewski. To carry the latter's analogy further, you can attempt to breathe through your esophogus all day, but swallowing the air will only cause pain and bloating - never enough gas exchange to function well.
I avoided this subject, because of a wish to allow others privacy, until the rash of law breakers last spring forced me to realize how far they were willing to go to get their way. The force was what caught my attention: their intention to break the law in large numbers, flaunt their actions and refuse to take any responsibility for it. I can imagine the outcry when and if anyone is convicted for that law breaking.
Natural family planning. It's different from "the rythm method." And NFP is only permitted for grave reasons, that is, reasons that threaten the existence of the marriage itself.