I never pretended to like things I didn't.. I mean it'd be part of a shaky foundation for any kind of friendly dynamic, to me. If someone's really enthusiastic about something- & I don't particularly care about it- I try not to be a buzzkill, & I'll occasionally ask questions around the topic - "active listening," I guess. Somewhere in there, I can typically dig out some part of the essence of the interest & find connections with things we're mutually interested in. Or I just listen because I otherwise enjoy that person's company, & I may playfully rib later on that I really can't wrap my head around the importance of said interest- but emphasize that I'm glad it makes 'em happy. If it's someone I don't give a shit about & for some reason *have* to be around (family/coworker/etc), then I just do the "active listening" part til I can physically remove myself. Sometimes the questions help me indirectly understand the other person in a new light, but most of the time, I'm just not there- and that's the point, at that point. I don't care to be, so I'm not.
At the end of the day, I won't lie about my interests or pretend to give all that much of a damn. It is possible to illustrate that mentality without being a jerk, too. People seem to perceive this sort of thing in terms of extremes. Either you're fake-happy-interested-an empty shell, or you're a cold-unfeeling-obtuse-asshole. There's a lot of gray area if you let go, & look around.
That said, I'm happier alone than I'd ever be if I pretended to be someone else for the sake of.. of what, even? Some vapid sense of acceptance? It has no meaning. It's about as valuable as the lies that would've fostered it. I'll take "awkward" silences any day.