I'm not sure exactly how I mean to present this question. It's certainly hypothetical, and I suppose personal input as to whether you'd get into a relationship such as this.
Example: I was watching the film Basquiat recently, and Jean-Michel meets a woman named Gina and they get into a serious relationship. This is at age 20, and if anyone knows about Basquiat, he dies of a drug overdose at age 28. JM and Gina date steadily for over 4 years, and continue to see other a little after, but JM is a very different person...artist and very much a loner in the middle of a billion people. However, if Gina had known that he only had 4 more years to live, would she have stuck around? More so, if he had proposed at age 20 and she knew there were only 8 years, would she have thrown caution to the wind and married him, or knowing the end would come, shy away from the relationship altogether?
It's almost a question "is it better to have loved and lost than never to have loved at all"...but not quite. There's a twist here and I'm not sure how I feel about it. It's hard to contemplate because it's not in our culture to give a death-date to a relationship from the beginning, though many think about. "Why get involved...it will just end?" But one step further. You have an exact date. You can get your calendar and think "well...I'm relatively free for the next six years, I don't plan on making any big moves, geographically or personally, so I may as well take up with this guy for the time being."
It wouldn't be all wine and roses, but it also wouldn't be all tears and slamming doors. Just like any relationship, but you'd have that light at the end of the tunnel. "He's acting like a child, but it's only another 2 years...what's 24 months?" You could start a countdown.
And if you're enjoying the relationship by the time the expiration date comes up? I'd say shake hands and part pleasantly. Find a next relationship or take some time to yourself.
This doesn't necessarily have to involve marriage, but I think it would be good if it did. You'd have all the balls and chains and couldn't pretend it's just dating. Same house, joint checking accounts, all the problems that accompany a marriage...and the tax breaks and insurance benefits too.
I think a problem with marriage this day in age, is that people are scared to commit for that long. It's so...undetermined. What if you and your spouse live to be 95? If you got married at 25...that's 70 years! Most people don't even live that long, let alone living with the same person day in and day out! That scares the hell out of me, I can tell you that much. When you look at a future husband or wife, do you want to be thinking "can I stand this person for 70 years?" Wouldn't it be much easier to say, "Can I stand this person for 7 years?"
Then within one life span, you can have upwards of 5 spouses, each one different and each marriage unique. It's like a burrito from Chipotle. Not every one is outstanding. But if you have a sub-par one, you think "well, there's always next time." And if you get a really good one, you can enjoy it and really appreciate it. Perhaps relationships should be more like burritos.
In other news, I think I need a cat.
I definitely need some sort of companion, and I don't like dogs, and any animal kept in a tank or cage isn't as fun as one that will sleep on your lap. I even have some names picked out. Except that my apartment doesn't technically allow animals and my room isn't big enough to let a kitty roam free and wild. Seriously though, there are times that I don't speak for hours at a time. I might mumble to myself every now and then, but I honestly don't think I've spoken to another human being since I hung up the phone with my sister last night at 11:30pm. It's now 3pm the following day. My vocal cords are going to stop working.
At least with a cat, I'd have someone to whom I can talk, even if it doesn't respond.
Now, I must study for my film test tonight.