Shared laughter can create closeness that serious conversations alone cannot manufacture.

Serious conversation builds one kind of closeness. Laughter builds another, and it is not a lesser one, because it requires enough shared reference and timing that it cannot be faked. Two people who find the same things funny have a private language, and that language does work that sincerity alone cannot do. It is why old friends can say almost nothing and feel entirely at home.

Do not treat the light friendships as shallow by default. And in a relationship that has become all logistics or all difficulty, look for something to laugh at together. The repair often starts there.