I’m afraid the answer is F.R.I.E.N.D.S. My sister and I watched it growing up, then rewatched it, the re-rewatched it, and now then have it playing in the background as I work. I have some problems with it but I’ve realised that memories of watching the show are in my head intertwined with good times with my family simply because they happened very close to each other — the same evening, for example — so thinking of one has often meant thinking of the other. I suppose I also like that all its seasons end on a happy note, which sometimes strains credulity but I think that’s been a small price to pay, these days, for some laughter and the knowledge that it will all end well.
As for films: I’ve watched several more than five times, but the ones I’ve rewatched the most are compilations of the actors Vadivelu and Goundamani. I’m not sure how familiar people beyond India are with how comedy scenes exist in our films. Watch few a dozen or so featuring the best comic actors of Tamil cinema and you will realise they’re drop-ins — little skits or vignettes that an actor and his crew will have crafted to be connected loosely or strongly to the film’s narrative at large but which can often still be removed without much consequence.
This has also allowed studios, network operators, and others to compile scenes featuring a single actor across films into a single YouTube video, often a few hours long. And I’ve rewatched those featuring the talents of Vadivelu and Goundamani (separately) several hundred times. In fact, I’d wager there isn’t a scene featuring Vadivelu I haven’t watched, and that would likely go for most Tamilians. I also know his lines by heart and they haven’t become more boring with repetition. I only know the names of a few films, however, but in Vadivelu’s case everyone knows that doesn’t matter. His scenes often stand on their own.