I felt like Gojo and Geto were the only ones who truly understood each other. They were both regarded as the strongest, and I feel like they were only able to see each other as true equals. Gojo was still friendly with the people at jujutsu tech, but he didn't have that same level of bond with everyone else that he did with Geto. That started to change after the Star Plasma incident, of course. Gojo became incomparibly stronger than he was before and Geto trailed behind. Gojo still considered him his best friend, but the time they spent apart grew larger as Gojo was sent on more solo missions, and they grew further apart. Geto was once considered the strongest alongside Gojo, but Gojo has long surpassed him.
So anyway, in a sense, you're right, but not really. Shoko was close enough to be considered a close acquaintance, or something similar like that, but they didn't share the same bond with Shoko. Sure, they were in the same year, but that doesn't necessarially mean they had to be close with each other, however, she wasn't *not* close enough with them to just be considered an afterthought.
"The only one i have" i have various of thoughts after rereading the jujutsu kaisen manga, but shoko's situation affected me the most. Throughout this time, was shoko just in the back of geto and gojo?