AR: “ One falls in love with the embodiment of the values that formed a person’s character, which are reflected in his widest goals or smallest gestures, which create the style of his soul—the individual style of a unique, unrepeatable, irreplaceable consciousness. It is one’s own sense of life that acts as the selector, and responds to what it recognizes as one’s own basic values in the person of another.”

Sex.

marry the mind and love the boobs, gently!!! -- j
.

Astoundingly enough, it's the first 30 seconds that make all the difference in the world. It's that first look that starts everything else. What strikes the fancy is still under study, but it is this concept that made speed dating an uncommonly effective matchmaking facilitator.

Seems as if I've covered all the mentioned bases, but then I've had more time and gone through more cycles than many on this list.
First big one was intellect and spirituality, second was physical, third was just because she was different than everything I was.
I am now pondering - and haven't experienced - actual friendship, which in turn takes me back to the beginning of the cycle.
I'm out of time and energy and money, but the fertile brain marches on.

So much to consider: One study confirmed that the skimpier the clothes a young woman wore at a dance club, the more likely she was to be ovulating.
There are lots of books and studies of your topic.

As I've aged and seen relationships formed and broken around me (relatives, friends, etc.), my question is why people are and remain attracted to those who do not treat them well or even abuse them.
Particularly, people get unhappy, divorce, and find someone else on whom to dump their baggage, and another unhappy relationship ensues..
So the question to ask is not, "what's wrong with you," but, "what's wrong with me that I keep finding and establishing intimate relationships with people like you."
If you truly love your self, then you should find a mate with that same characteristic. Be choosy; expect the best.

Love your story. Nowadays I have heard a young man say, "Marry the ass; buy the boobs." Some things never change-

Growing up with brothers and sisters has a lot to do with learning to interact with the opposite sex as equals during the courting process, too. The only child is often a bit more entitled/demanding and less sensitive, IMHO.
Courage is important. The snoozer looses.

On the other hand, there's an old story of a wealthy young man who was considering marrying one of 3 women, but he was worried his wife might squander his hard earned wealth. So he gave each $1000 to see what they would do with the money.
The first bought herself a lot of jewelry and clothes and got nothing for him.
The second bought an equal amount of similar stuff for her and him.
The third invested the money and made a significant profit, then treated both to something nice with that profit..
Which one did he marry?
The one with the biggest boobs.

Rand noted that there are critical differences between friends and lovers.

Holding the same fundamental values is a necessary condition, but is sufficient only for friends. For true love (as Peikoff explains), one should see the other person as representing the sum of his top values, see him as irreplaceable, and see the need for a sexual connection.

Thanks, Technoacracy. This is a good answer, and understandable. I don't believe it's random chance (nothing ever is), but if there is a similar value hierarchy like IR1776wg said and as is consistent with Objectivism, wouldn't each partner's explanation necessarily be similar, though not the same?

I had assumed that sexual chemistry was a large part of it.
2. That makes sense, and also explains a lot about the relationships I've seen.

1) Initial attraction is sexual.
2) Long term requires a very similar hierarchy of values which requires both of you to place a higher value on reason than on emotions. Not easy but doable.

If anyone here could definitively answer that, they could put every dating service in the world out of business. Making themselves extremely wealthy at the same time.

With any relationship involving two people you can't quantify the why's exactly from outside, only they can. And even their answers are subjectively theirs, their partner's are likely to be very different even though they share the relationship in common.

Could you explain? I don't understand.

It's subjective