Jay just wants to be part of a family again.
Family has consistently been a central theme in Jay's arcs. From the first season, where he has to handle his annoyance at his parents, through Skybound as he learns the truth about his birth, to Prime Empire where he uses his own experience to help Unagami...
And that's just thinking about Ed and Edna. Jay's family with the other ninja is just as important. They mean everything to him.
So to have that family completely stripped away, and then watch from the sidelines without being able to fully join in... ouch. It definitely changes the way I watch that scene.
When I first saw that part of DR S3 P2, I thought it was Jay's attempt to keep a distance from the other ninja. He was catching feelings for Nya, but he didn't want to get attached to anyone, so he abandoned them for fear of making himself vulnerable. And maybe that was part of it, but after hearing his perspective here, it seems even more that Jay wanted to join the ninja, but he was so afraid of being rejected that he left before they could turn him away.
Because Jay's other common arc? It's his fear of being ignored and shoved aside as useless or unworthy. He's constantly putting up a facade to convince himself and others that he "deserves" to be on the team, even though they just want authentic, real Jay.
