There are exceptions to every rule. What numbers I've found on success rates for living together first vs marrying show living together fails more than marriage.

So, in giving advice to a stranger from a reddit post I say go by the numbers rather than giving a reflection of ourselves. I haven't seen any numbers on length of dating, but the general rule in my part of the world is that being obviously a forever match at about six months or so is a good indicator. Having issues that early is, too.