@Hamiltonian299792458 I noticed that friendship dynamics changed a ton after school. Nowadays I tend to float between groups based on convenience (lectures, labs, sports, etc.) more than anything else, and move on fairly quickly once our paths diverge. And three of the four people I'd say I know best at the present are international students who aren't even in the country for half the year. I'd say that I haven't had a best friend for about five or more years, but certainly wouldn't view it as a bad thing!
(Might also add that I found it insanely hard to make friends during the first term of university, but it got easier once I started taking myself less seriously and shook off some of the "new environment"-nerves. Perks of being an awkward physics student, right?

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