Dear LIB readers: How long is a 'long enough' courtship

I met my fiancee/boyfriend in July this year and we would be getting married by end of october or december this same year (not decided yet) we have both met the parents and we are planning our wedding. And am certain in my heart that he is 'the one' and he also feels the same. But when people ask how long we have known, I know it'll be absurd to them when they hear the short duration. But does the courtship duration really determine how successful the marriage will be?