Im lucky to have the same group from standard 8 in 1995. Over the years we studied at different universities but would meet up weekends and evenings. from 2000-2010's email then gmail was our default chat. last few years we have a whatsapp group.
i define them as friends as we have all attended each others weddings, Any birthday is a default open invitation. Unanounced visits, regular braais. never have arguments.
interestingly, we started with some girls in our circle, but they faded. I reckon guys are simpler beings.