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Clara has repeated that story in many streams, she often just wants to be friends with a dude, but the dude wants more, and the friendship is ruined. Basically... Clara is hard to get; she doesn't like when men misinterpret her signals and want something more than a friendship.
With that attitude Clara will never find a partner... but Clara is also mostly vegetarian, allergic to going outside, hypochondriac, and a bit crazy that she fawns over an AI of a fictional Asgardian, so yeah, it's complicated.