On this daf, we find that one may not even get married during the moed, since he needs to be happy because it’s Yom Tov; even the mitzvah to rejoice at a wedding interferes with this, since it is a different simcha.
From Shabbos Mevorchin of Rosh Chodesh Elul until Shabbos Shuvah, Rav Isser Zalman Meltzer would deliver words of mussar at Yeshivas Eitz Chaim each Motzoei Shabbos.
Following is an example of one of his brilliant discourses imparted at that time: “It is now Shabbos Mevorchim Elul. We must wonder about the proper place of Elul in relation to the Yomin Noraim. The answer can be gleaned from the Netziv of Volozhin that the mitzvah to be joyous on Yom Tov isn’t relevant to tosefes Yom Tov, the time during the weekday before Yom Tov that we can opt to add to the holiday.
“He proves this from Kesubos 47. There we find that a father can give his daughter over to the agents of her future husband on Shabbos or Yom Tov. Tosafos wonders about this. Since giving her over in this manner makes her considered married, how can we give her over if it is forbidden for her to get married on Yom Tov? On Moed Koton 8, we learn that one may not get married during the moed from the verse ‘Vesomachta bechagecha – And You shall rejoice in your holiday,’ which precludes rejoicing in acquiring a new wife during these days. Tosafos answers that the Gemara means that her father gives her over during tosefes Yom Tov, the time added to the Yom Tov. Clearly, the joy of the Yom Tov is not extended to the time that we add to it. If it were, it would be forbidden to marry even during tosefes Yom Tov.”
Rav Isser Zalman continued elucidating in his hallmark manner: “But this only refers to the simcha of the Yom Tov. The eis ratzon, the auspicious nature of the Yom Tov, definitely also extends to tosefes Yom Tov. Not only that, but the added part of the Yom Tov is actually more of an auspicious time than the Yom Tov itself. And the same holds true for Elul. Just like the main character of Yom Tov is joy, the main component of the Yomim Nora’im is trembling from judgment. But this is not yet relevant in Elul, just like the joy of Yom Tov doesn’t yet apply during tosefes Yom Tov. But the auspicious nature of these days, the ‘dirshu Hashem behimatzo – seek out Hashem when He is found,’ which relates to the Yomim Noraim, is more palpable during Elul than during the actual Yomim Tovim. This explains why Elul is the ‘chodesh harachamim vehaselichos — the month of mercy and forgiveness’” (Me’ilo Shel Shmuel, p. 281).