Nearly every line here is the set phrase 오며 가며, built from 오다 and 가다 with -(으)며 "while," meaning you cross paths in the ordinary course of coming and going: 오며 가며 몇 번은 본 것 같아요, 중간중간 오며 가며 인연이 있었구나. It is the standard way to describe a loose acquaintance you have never properly met. The bare -며 가다 outside that phrase just means going along doing something: '하늘을 가르며 간다', slicing through the sky as it goes.