Your fiance is wrong, wrong, wrong, wrong. Some women orgasm quickly, some slowly, some in between and some not at all. I have been with all types. Maybe another guy with different skills and/or different physically could have got different results. I don't care. It is what it is. I do try hard to make her happy, though, at whatever rate (being married for a long time, I am mostly speaking of past situations.) Love is mostly separated from a woman's ability to orgasm at any given rate.
So his boastful friends have girls falling in love with them all of the time? He did say the girls orgasmed fast and he did equate love with fast orgasms, did he not? I'll bet that is not the case.