This law is very valuable. I can't remember where I heard also another piece of advice (sosuave, Molyneux, or the Briffault's law page --bankok Thailand writeup), but it was about how Women...ONLY put her BLOOD before you, I don't care if it's her 3rd, 4th, or 5th COUSIN, man or woman, he or she, is coming before YOU, the non-blood-related individual forever stranger, who may or may not be married to her currently. Don't know where I got that from, but it's true to an extent.
Just because you're married to your "spouse" or long-term-girlfriend, does not at all, in her mind, make you "Blood Related." She will drop you like a hat, without warning, just because, in her mind, you are not her REAL family, which is her mom, her dad, grandmas, granddads, aunts, uncles, cousins, distant cousins, and maybe even distant distant cousins, and on and on if she's crazy, and like studied her entire family tree on ancestory.com or something.
This is evident by my mom's divorce from my father, and her not really caring about deaths in his family since the divorce.
The ONLY reason she cares one iota for me or Half of me is because I am half of her, By Blood. I don't believe in all this step-mother truly loving her stepson, adopted son etc etc as if blood, sure there are exceptions, but let's get real, we are talking biological WOMEN here, and how they operate.
We, as men, can make that jump to treating a woman or our best buddies in COMBAT, you know Friends that would stand beside you no matter what goes down, we as men, consider them as fvckin blood brothers, even though technically they're not. Women, this could never be the case. Most women's friends would RUN at the first sign of true hardship from said woman, or a life n' death situation. Sure, there are women cops that shoot assailants and save others, but exceptions exceptions, we're talking about on the whole, they will drop you to save themselves, if you're not of their blood.
So every man that a woman takes to the cleaners in a divorce, she drops not only him but All of his blood relatives, and retreats to All of her blood relatives.
So, to take from this, I know, that back in the olden days, MANY of the first Americans born on this soil, married cousins, first cousins, second cousins, and on and on. They stayed close within proximity, and the marriages lasted minus going off to fight the Civil War and making her a widow. It was common up until about the 1940s I'd suppose 50s that marrying COUSINS become taboo, or shunned.
Now, when a woman marries, the man's lineage she is marrying into is SO vastly different than hers, she MUST hold her connection to said man with a nano-grain of salt. He is NOTHING other than "can he make me laugh" and "how much money can I acquire from this stranger!"
This is the state of affairs. You're not her "blood," she knows it, internally, maybe consciously, and therefore, you're NOTHING. Briffault's Law applies to most American relationships today as a result of this non-blood relationship.