I got married because of the symbolism of it and the benefits that come with being married. I wanted to be able to say "my husband" so that other people would realize the commitment level we had.
All that said, I have to agree with Charletnarouh about the divorce rate being so high that saying your "married" doesn't mean much anymore. People jump in and out of marriages like they're nothing.
I also agree that there's no absolutes in marriage. I love my husband deeply and intend to be with him forever. However, as said, shit can happen. When things get tough I made the promise to work on those issues rather than jump ship. If all the hard work in the world won't save the relationship, then I guess that's how the cookie crumbles. All I can do is the best I can do to keep my marriage together. I know he does the same.
As for the religious portions of marriage, that doesn't really apply to me at all. I got married in a non-denominational ceremony. I tend to think a lot of people who are religious stay in loveless marriages because of the belief in the system. I have family members like this. What a shame to spend your life miserable with someone you don't get along with. So in that sense, I think the idea of staying with someone you don't love and don't get along with because of marriage is not the greatest. Try to work it out? Of course! But if you've done everything you can, don't beat a dead horse.