What's the REAL key to sustaining a relationship?

I hear select friends talk about the secret to staying together all the time. Some of those same friends are single now. I'm not throwing a shot at them. I'm just sayin.'

How do you really sustain a good relationship, whether that be a marriage or a serious dating situation? I was recently communicating with the mother of an ex-girlfriend of mine. I consider her to be like a mother to me. Anyway. I was going to ask her what the secret was, being that she's been married to the same man for many, many years. Then I thought about it. That would be unfair to ask her that because she's truly married to a very great man. He's got many sides to him too. So, I'm sure there is never a dull moment in their marriage. I know there was never a dull moment when I was around. Plus, a lot of older couples were able to stay together because times were different back in the day.

That was before facebook, twitter, email, myspace and so many other things that tend to play as a distraction in certain relationships these days.

But I'm really talking about the countless relationships that don't make it after a seemingly long run. Everyone isn't a great communicator. Everyone doesn't like to party or go out a lot. Bascially, everyone isn't into the same type of things. Most people act as if they can deal with select differences when meeting someone interesting at first. Actually, most relationships start out relatively well...mostly because a lot of people ACT the part of the significant other well.

Then, time goes by and the real THEM comes out. Sometimes that means that they have a bad temper. Sometimes one realizes that their significant other isn't the smartest or most romantic person around. That doesn't mean those men or women don't have other great qualities.

So, what keeps people from seeking what's missing in their relationship? I don't mean cheating either. I mean, what keeps a people from thinking they need to be with someone else after being with the same person for a seemingly long stint?

How do you look at the same person for years and still want to see them for another 20 or so years? A lot of people have a hard time keeping an old relationship new. I guess the real key is making sure you know a person before you begin to think about marriage or the years to follow.

All right, I'm through rambling for now. What do you think?