Related על מגילה 4:3

They do not make fewer than seven stops during funeral processions, and they do not say the blessing for mourners with less than ten [present] (Meg. 4:3). And the amidah may not be said with less than ten, and mourners do not count as part of the minyan. We do not say the blessing of the bridegrooms with less than ten, and the bridegroom is part of the minyan. The blessing of the bridegroom may be said either at the engagement meal or at the wedding meal, either on a weekday or on Shabbat. Rabbi Yehuda says, if new people came, we may say the blessing of the bridegroom, and if not, we may not say the blessing of the bridegroom.