Ok, here goes for my first theory!
I read some time ago a note about statistics in WOT, and that got me thinking about something statistically, that is the fact that every "good" caracter seems to have a romantic intrest somewhere. Let me explain: Perrin has a wife, Rand has three, Mat will eventually get one (against his will), Egwene and Gawyn, Moiraine and Thom, Siuan and Gareth, possibly even Berelain and Galad.. Even secondary caracters like Bain, Chiad and Gaul, or the Ashaman and their Aes Sedai in WH seem to spend most of their time on personal affairs rather than on preparing for their DESTINY. In the later books, there is almost only detail, detail and more detail about some personal aspect of the caracters, and then a big exciting scene at the end that lasts one or at most two chapters. I don't know the percentage of hardened bachelors in real life, but it certainely isn't only 5% of the population.
On the other hand, members of the Dark don't seem to have any intrest at all in pursuing a relationship with someone. I guess that's pretty natural, considering they're all greedy power-crazy suspicious caracters, but there doesn't seem to be to have been a single Darkfriend that's married in the series.
After all of this hard thinking that partially melted my brain, I thought that there should be a reason for this enormous imbalance in the two sides of the upcoming Battle, and for the fact that three quarters at least of Jordan's series is devoted to the caracters' relationships (I'm not saying that's bad, I just think there's a bit too much of it at times). Maybe this apparent weakness (spending all their time drooling at each other rather than snarling at the ennemy) is actually a strength, that is, the couples (or quadruplets - is that a word?) will stick together during the Last Battle, and will defend each other while the Darkfriends are stabbing each other to get at Rand first.
Well, that's my two cents. If you can do something with it, I will be very pleased 
StoneDogAiel says: I like that. That is one of the most original theories I've seen. I think that it is very likely that your theory is correct. The bad people won't have anybody to watch thier backs. I agree.
Comments
Well, it sounds pretty good. We have certainly seen plenty of examples are DF's killing their own families for personal gain. Good job.
Aviendha 
Excalibur's Mississippian
Druid's cute, dutiful, if pert, niece
I think you did a fine job on your first theory. I never paid that much attention to all of the relationships of the dark friends. Good job!!!
O
Very good theory, and in a way, similar to what we saw at the end of Winter's Heart. The Forsaken all showed up, and were turned away, largely because of the circles the people had formed.
KLitke7967
In general, your theory works, but this cuts out Melindhra, Mat's girlfriend that was forced to try and kill him, and a few couples whom Liandrin and company had to stay with while. One in Amador, and another in Tanchico. Altough they were one sided relationships, Graendel and Rhavin did have quite a few. In general this theory does seem correct for most of the active Darkfriends.
...With the possible exceptions of the People that Liandrin and her crew stayed with it seems that all other Dark Friend relationships are based on dominance, power and lust.
The fact that the good guysbase their alliances and love relations on trust and concern for one another will probably be a very big advantage.
Bravo good job.
Sooner or later it all connects back to itself.
the black ajah in the green ajah have warders, and i'm sure that, knowing the greens, there's something more goin on...
___________________
Evilmonkey
"Madness waits for some. It creeps up on others."
-Lews Therin Telamon
I would like to point out that our sampling of good guys is much larger than our sampling of bad guys, and we are seeing the world from the good guy persective for the most part. Even Trollocs have to have some social relationships, how often have they bumped into only one of those things? Dark friends are still people, and they need social settings.
Burasco
I think the reason we're seing so many goodguys relationships, and so few badguys falling in love, is that it wouldn't give the right feeling.
If you see two mosters kissing, you dont think "Oh, how romantic!"
, you would rather think "eehw!".
But I must say that Jordan do have a thing for coupling characters.
da'covale d'Rie Bolmdahl 
Deyeneiye, dyu ninte concion ca ye (no, tia Rie Bolmdahl)
I'm sleepy.
currently: away
A few notable exceptions may be:
-Cadsuane
-Elaida (not technically a DF, only a puppet)
-Elyas
-Lini
-Tenobia (unless you believe the wild rumors that all Basheres are DFs)
-Tam al'Thor (true he did have a wife, but no love interest currently)
-Noal (Jain) Charin (Although he may be under Ishamel's influence still)
-Aram (although there are theories that he is a darkfriend too)
Of course your theory does seem right in the preponderance of cases!
AOBtD
Bearer of the Mysterious Name
AOBtD
It`s frustrating when you know all the answers, but nobody bothers to ask you the questions.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
The only exeption I have red about is in the War of the power time. There was mentioned about a lovestory between Ishamael and LTT`s sister Ariel Sedai
Sa La Ve! Beautiful you have a good point i mean i cant think of greandels "pets" being of much help.
An Opptimist Knows The World Is Good... A Pessimist Fears This Is True.
IM IRISH!!
Lanfear is the only one of the main dark friends that I can think of that has actually sought after a romantic relationship. I really do believe that she felt love for Rand but he obviously did not reciprocate. I like the theory. I've always thought that the main weakness in the forces of the DO is that they can't trust one another. I believe that in order to win the DO would have to find a way to help his forces work together. However,because they won't they will not have a leg to stand on.
i think it makes perfect sense in alot of ways. We've seen that both sides of the power, when used alone, can be beaten. but what about if the two were used in perfect tandem, doing the same thing at the same time? maybe then it'd be more powerful than the darkfriends. it would also tie in with the symbol for the aes sedai. back in the age of legends, when the aes sedai were at the height of power, it was a symbol for both sides of the power being used to the same end. but when the male half was tainted, it kinda lost that meaning. it would make sense that for the aes sedai/ashaman to win, they would have to change things back to the way they were at the age of legends.
The dark guys who had relationships drew NO strength from the companionship, its more like they scratched an itch.. or did a little work.
Proof of this theory can be seen when Rand and his 3 gals are joined together. The golden bonds they can see flowing between them all. (sidenote: black bonds to the DO)
Jheran...
Insert witty remark here
Valda was married at some piont if he has a family for the Fades to kill. He says that a Fade took his daughter on her wedding day at some point in the series.
The brain-dead master of sleep!
I agree for the most parthowever, what you said about the evil characters not pursuing relationships is not entirely accurate. Lanfear quite obviously tried to pursue one with Rand, Hadnan Kadere was infatuated with Isendre, Melindhra was with Mat, and I am sure there are others that I cannot remember
I would have to say I agree with the premise of your theory, and to go even a bit further, I think the warder bond will be one of the keys to winning the last battle. I'm not sure how exactly, but we are seeing a whole lot of bonding going on in books 9 and 10, and we know that this is something the Forsaken are not privy to. I believe it is in tPoD that Moridin comments on this particular discovery of these "primatives", and Graendal makes a similar observation somewhere as well, I think.
I don't call rands situation a quadruplet. Its either an orgy or a headache depending on the time of day.
Ipkin Styld
Channeling Borderlander
Slayer of renegade Whitecloaks
Kicker of major Trolloc Rear-end
Warder to the Fantabulous Missa Sedai 
Drinker of spirits 
Eternal watcher of the Damned 
Evil Git 
Chief of the movement for Narg Superiority 
Death to all camels 
I've always been afraid of clowns. I think it goes back to the time I went to the circus and a clown killed my father.
Hmm..