I think Jess' tragic backstory mainly exists so he doesn't come across as just the guy trying to break up Rory and Dean

Maybe this is an unpopular take, but I've never put as much stock into Jess' tragic background as a lot of the fandom seems to.

Obviously it's sad that Liz neglected him and Jimmy walked out. I'm not saying those things wouldn't have affected him.

What I've always wondered is if the writers gave Jess that background because of the role they wanted him to play.

Jess is introduced as the new love interest who's openly pursuing Rory while she's still dating Dean. Without any extra context, that's a character who could've easily come across as just the guy trying to break up a relationship. Giving him a rough childhood immediately adds another layer to him. You're not just watching a bad boy flirt with someone else's girlfriend, you're watching a kid who's never really had any stability or guidance.

The reason I don't put as much weight into that backstory is because I don't think the show does either.

When Liz finally shows up in Season 4, she's almost nothing like the person Luke and Jess had spent two seasons describing. Before she appears, she's painted as someone who neglected Jess, bounced from relationship to relationship, had drug problems, and eventually sent her own son away because she couldn't handle him anymore.

Then she arrives and the show treats her like this quirky, harmless Renaissance Faire hippie with T.J. It never really feels like we're supposed to view her as the woman who caused so much damage in Jess' childhood. If anything, the show seems to want us to like her, or at least not think she's nearly as bad as Luke and Jess had made her sound.

That's why I've never really invested as much in Jess' backstory as a lot of the fandom does. If the writers wanted it to be this defining part of his character, I feel like they would've committed to the version of Liz we'd been hearing about instead of softening her once she actually appeared on screen.