I want to get married because I want to be the father figure of a functional family unit. The failure rate of marriages has largely to do with people who make really bad marital decisions. Sometimes, they just fail because of things beyond either spouses' control. It's a chance I'm willing to take.
Getting married just so you can have sex is the dumbest thing I've ever heard though. If you're christian, I'd suggest you commit a serious sin and have sex with someone RATHER THAN marry just for a sexual encounter, cause in the end, the latter would bring even more anguish.