I wouldn't put it in such B&W terms.

My mother and stepfather are 29* Cancer and 18* Aries, respectively.
I am an Aquarius, and in recent years I have more & more begun to date women with an abundance of Taurus. I think the reason for that is maturity. Once you learn how to deal with that which you don't understand, or that which occasionally rubs you the wrong way, it can actually be very rewarding. The key is developing patience. You might find that if someone has a strong square to you, that just behind that square is a much better aspect dying to get out...but youhave to defeat the square first. It just represents a kind of challenge. Squares in a single chart can actually yield a person with above average capabilities, and endurance, and insight. The conflict has forced them to develop good qualties out of hard work...and eventually it pays off.
If you have a lover with their Sun square yours, if you have an abundance of trines or sextiles a conjunction or two between "nice" planets, then both of you might stick around and really learn that "love really DOES hide in molecular structures!" - Jim Morrison.

My brother is an Aries.... His love of his life is a Cancer.. They been together for a few years, and seem to get along.

As a Scorpio I always wanted to date my square (leo or aquarius) as I've always been strongly attracted to them. But I'm also easily intimidated by their strong, fixed nature. Maybe this attraction is due to my ascendant and mars being in Leo. I thought maybe that would smoothen the square a bit and make them appear more approachable but there still always seems to be underlying friction. Aquarians have figured prominently in my life, but usually on a friendly basis and never romantically.

As far as famous couples go I've noticed that while "successful" scorp-leo couples do exist (schwarzeneggers and clintons), I've yet to find a stable scorp-aquarius couple, much less an unstable one. The sarkozy's were the first scorp-aquarius duo but they're history now. Their relationship made somewhat sense considering cecilia sarkozy was a leo-ascendant scorp (like me) but eventually it faltered. I'd be amazed to find a stable aquarius-scorp couple. I've seen almost all permutations of the horoscope save that one.

I'm a pisces and I've had a few relationships with sag. Best friends and lovers. I also have a lot of sag in my chart, though.

i just started seeing a really nice person and our synastry has an abundance of squares..

but the striking ones being:

pisces sun sq gemini sun
cancer moon sq aries moon
my taurus venus sq his leo saturn

he is the watery one. i tend to think that when the square aspect comes into play between couples, instead of looking at the friction, look at the common mode that is in the signs. for example, both of us are really active and love doing things but he tends to get sidetrack by his moods and whims while i just want to get straight there to do it no matter what it takes. the merry-go-rounds we take are frustrating but so much fun! As long as we don't take things too seriously (for the activities) but we feel comfortable with each other and trust and are honest.

He can get very critical and teases harshly sometimes and I tend to take things very very seriously. but i tell him about my sensitivity and remind myself it's only a joke then it's ok..

one of my best friends has her virgo sun and moon sq my sun but then again there are alot of really good aspects for the rest of the chart so it works out! astrological compatibility is good but it can be boring, non?