Can someone explain the logic behind this to me? And why every jg does this?

Why does every jungler ignore whoever right next to them??? Ok, if you see someone getting their ass kicked and pinging repeatedly, and you are literally RIGHT THERE, wouldn't it make more sense to HELP them rather than walk to where they're fighting and stop to stare? Every jg I get paired with does this. They walk to where i'm fighting, stop and stare for a couple of minutes, and then leave. So then whenever the dude I'm fighting get's super powerful, I spammed in chat (mainly by the jg player) with the "You let him get fed so I'm gonna report you!" song and dance. Here's how I see it: You literally sat and watched me die over and over rather than help, so when this person goes around one-shotting everyone on our team, you have no right to complain. No exaggeration when I say this, they literally come over to WATCH ME DIE. This aint one-time stuff either, every time I get paired with a jg who stays close to my lane this happens.