I hereby proclaim my rational rejection of interpersonal sex!
The idea of two (or more) people being totally in sync with each-other's sexual needs is becoming an ancient myth. Yes, it's possible (or so some people claim), but it's a huge gamble, and at what cost? And you can never be truly, sustainably happy if your happiness depends on someone else - someone who could leave you or change or get sick or suffer an accident at any time. And someone who is your ideal romantic partner is not necessarily an ideal partner in all other things.
The more sophisticated a human mind becomes, the more individualistic it becomes, and thus the greater is the sacrifice it would need to make to adapt to his or her sexual partner(s). There is something downright disgusting about a caricature of a millionaire paying someone else to tie his shoelaces or wipe his butt for him, and I am starting to feel the same way about sex. Self-reliance (i.e. masturbation) is starting to seem a far more rational, creative, and dignified outlet for human sexual urges (if they can't be turned off entirely).
I am
a big fan of natalism and increasing the human population, but sex and procreation have become two completely different things. A sperm donor who has never had interpersonal sex or even hugged another person in his entire life can father millions of children (if his genes or other economic incentives are deemed so desirable), while a prostitute who averages dozens of different partners a day can die completely childless!
A person not wasting his/her time, money, and emotional energy on other romantic / sexual partners will be able to allocate more of those resources toward more meaningful things, including enjoying solo-erotic activities with complete emotional peace and fulfillment. Instead of wasting your life trying and most likely failing to have a soul-mate, you can instead strengthen yourself as a more complete individual, and thus a better human being!
It is natural for people to have a lot of love they want to give to others, but there are far more rational and rewarding outlets for that love than sexual relations: art, career, platonic relationships with one's intellectual peers, parents, and most important of all - children. With proper and gender-equal economic incentives for people to have children, a sexually inactive single parent would be far more likely to be a better parent because s\he would choose additional parent-figures for his/her children (tutors, homeschooling partners, etc) on the basis of their benefit to the children rather than to him/herself. In fact, concerns over future sexual attractiveness and freedom to pursue future sexual conquests is the main reason why people end up having fewer kids!
The economic benefits of interpersonal asexuality are unbelievable! It seems that some people waste half of their lives just to be more desirable to potential sexual partners, or to deal with the consequences of their past sexual passions (STD's, unwanted children, unhappy families, etc). Limiting yourself to occasional masturbation (which is no different from any other bodily function) makes a person healthy, wealthy, and wise - and those things should be particularly important to an atheist who enjoys life and wants to prolong it as much as possible.
Imagine being on your deathbed at the forefront of the 22nd century, desperately looking for a bank that would give you a loan for an organ replacement surgery necessary to save your life, knowing that it would make a difference between possible immortality in a holodeck-like paradise that's better than anything we can today imagine and complete and total demise. As one bank after another rejects your application, you are going to seriously regret all the time and money you've wasted hanging out with your "cool" friends in bars trying to pick up easy women, or sitting through chick-flicks / guy-flicks you don't enjoy, or shopping for a new fur coat for your wife...
Sure, materialism isn't everything, even if your existence in this materialistic universe may depend on it, but even subjective happiness can be more abundant if you just overcome your monkey-brain's irrational desire for interpersonal sex! Imagine all the great things you could learn by choosing the people you interact with on the basis of intelligence and other constructive benefit rather than sex or popularity (most nonsexual relationships are based on advancing one's social status, with sexual desirability being the primary motivator). In comparison to that, wasting one's time, money, and mental energy on romantic love or sex seems like subhuman stupidity!
A self-esteem boost that is obtained by appeasing your irrational emotions displaces the potential for boosting your ego through far more substantive accomplishment. I wouldn't trade even a minute of my intellectual self-expression even on this silly forum for an hour of sex with the most desirable sexual partner(s) this world has to offer! The knowledge that I intake on this forum will benefit me for as long as I exist, and the ideas that I create could last as long as the human civilization!