I agree about the similar interests. There are plenty of exceptions, but if we're going with stereotypes, most women in general prefer co-op experiences to competitive ones and co-op is the foundation for a good relationship. Sometimes you want to get the health pack, but she needs it more, sometimes you don't want to do the chores, but she needs the personal time more, it's the same deal.
My girlfriend and I make a great co-op team because we have two completely different styles of play which tends to make us really good at backing each other up and that's how we are in the rest of life.
Almost everyone can find games which work for them, Facebook is proof of that, it's just about not seeing it as a hardcore commitment and more like a fun way to pass the time, sometimes together.