I think a low-commitment will-break-at-slightest-strain marriage (or other long term committed relationship) is ok if you go in with your eyes open and decide that's what you want, I just don't think people think about all the bad stuff that can happen in life when they make that sort of commitment. Though after being together for ten years we'd already dealt with enough conflicts and tension that we had a system in place for working through stuff, which has worked reasonably well.