Many years ago, I attended Shabbos sheva brochos on Shabbos Parshas Vayera. The chosson and the kallah were talking to each other all the time even when rabbonim were speaking. At the beginning of the parsha (Bereshis 18:1), the Torah tells us that Hashem came to Avraham Avinu to be mevaker choleh after he had his bris milah (Rashi ibid.), but we are not told that He carried on any conversation with him at all. When one is together with a dear friend, even if no words are spoken at all, the presence of the friend gives one chizuk and puts him in a cheerful mood.
The Gemarah (Nedarim 39b) tells us that reason for the mitzvah of bikur cholim is to heal the patient. Rabbi Akiva had thousands of students, and he noticed that one of the students was absent for a few days in a row. He went to his dormitory room, gave him a clean pair of pajamas, cleaned the floor, opened the window to get fresh air, and gave him medication (ibid. 40a). The Rema (Shulchan Aruch, Yoreh Deah 335:4), the comment of the Ramban on that Gemarah is quoted which says that if one visits a choleh and does not offer a tefillah that he should get better, he has not completely fulfilled his mitzvah of bikur cholim. One is obligated to do the maximum he can do in order help the patient recover. Today if someone is sick in the hospital, the medications, the cleaning of the floor, the change of clothing, etc. are all being taken care of by the doctors and nurses. We know that if a patient is in good spirits, he will recover sooner than if he is depressed. The only thing left for us to do for the mitzvah of bikur cholim is to cheer up the patient and to offer a tefillah. When Hashem comes to visit the patient, that itself cheers up the choleh even if no words are spoken at all.
If the chosson and kallah are really in love with each other, just by sitting next to each other, even if no words are spoken, they are cheering each other up. The Gemarah seems to imply that on the sholosh regalim there is a mitzvah of simcha because we are all obligated to visit the Shechinah in the Beis Hamikdash, i.e. to be oleh leregel. The Gemarah (Moed Katan 14b) states that a kohein gadol all year long has the mitzvah of simcha which the rest of the Jewish nation only has on sholosh regalim because the kohein gadol has the responsibility to be in the Beis Hamikdash all day long to supervise the hakrovas ha'korbonos. Just being in the presence of Hashem, even when no words are spoken, puts one in a state of simcha. In Tanach (e.g. Ruth 2:4) we find that when one would greet a friend, one would say “Hashem imochem”. Today we say shalom aleichem because Shalom is a nickname for Hashem (Shabbos 10b). When the Shechina is with someone, its presence will put him in a happy mood even if no words are spoken.
When it was my turn to deliver a drasha at that sheva brochos, I had a yetzer harah to say this dvar Torah, but I realized that it would not help because the young lovey-dovey couple would be chatting with each other through my drasha as well!