A wedding is an amazing time, and unfortunately it is also a time when people who you do love dearly, and who all have their own ideas of how close they are to you, find themselves being (intentionally and unintentionally) measured against others, and sometimes this is unwelcome. Additionally, man-woman couples who may not ordinarily think very much about gender roles can be surprised by the amount of assumptions around gender that accompany a wedding.

If, by chance, your friend sees himself as "one of the girls", and you don't see him like that, you may want to clear the air. On the other hand, if he was just ranking himself as closer than he actually is, what he may need is the explanation that you are embracing your fiance's mom as not just the mother of your future husband, but as a second mother. Either way, the choice of who to include in which wedding preparation steps is yours.