I have terrible memory generally but I can recall how I met most of the friends I've made in adulthood, conversations we had etc. the same way you seem to do.

I have terrible memory generally but I can recall how I met most of the friends I've made in adulthood, conversations we had etc. the same way you seem to do. This is a mnemonic device though. The person is the device. I see them (or think about, talk to them, etc) and those memories come back kind of like a stream of things related to them.