I feel like for me getting married is more of a way to celebrate and share the love of our relationship with family and friends. It also ensures all the legal mumbo jumbo like being able to visit in the ICU or make critical medical decisions (god forbidding htose ever happen, but you know what i mean). Marriage is also a way to cement a commited relationship, because while you can easily walk away from just a regular relationship, with marriage (to me) there is a lot more invested into it. I can't really explain what I mean too well though so hopefully you understand...I also view marriage as something final, and htere is no walking away. If things get rough you do whatever you have to inorder to make it work. (but again, that's just me).
ok hope that helped somewhat...even though it probably confused you more