So long Creek. Buh- bye Buffy.

It's been a hard week for 20-somethings.

They're having to kiss their youths goodbye with the series finales of two longtime favorite TV teen dramas, Dawson's Creek and Buffy the Vampire Slayer.

Last Wednesday's two-hour finale of Dawson's drew a network record 7.3 million viewers to the WB, which Dawson's helped establish and define.

(For those of you that missed it: Jen died, Joey picked Pacey, Dawson is executive producing a show called The Creek and Jack and Deputy Doug are an item.)

Tonight's finale of Buffy is anxiously awaited. How will the beloved teen fantasy drama wrap up -- will Buffy be able to save the world . . . again?

In the ways that the break-up of the Beatles, the death of Kurt Cobain or the closing of the Palladium signaled the end of earlier pop culture eras, the finales of Dawson's and Buffy are signaling the end of the teen period of many Gen Y's lives, forcing them finally to grow up.

For high school and college students nationwide, the shows defined them -- in occasionally absurd and angst-filled ways -- and fostered obsessive devotion to watching them.

From the night that Buffy premiered -- as a mid-season replacement on the (then) fledgling WB network in March 1997 -- it was clear that the show was a metaphor for growing up.

Buffy feels like it's the end of the world when she's grounded. And it literally is.

Buffy's college roommate is not only annoying, but also physically sucks the life out of her.

"I've always been amazed by how often I identified with what the characters were struggling with," says Maliha Farooq, 23, a high school junior in Edison, N.J. when the show started, now a marketing assistant in Boston. "It was truth, hidden behind a protective layer of fantasy and camp."

Dawson's premiered in January 1998, also on The WB, and -- because of its semi-realistic portrayal of teen life and concerns -- instantly became one of the most-talked-about shows in high schools, especially among girls.

"For the first half of the first season, you literally could not turn around at school without hearing at least five groups of girls talking about Dawson's," says Margaret Lee, 22, a Vermont high-school senior when the show premiered.

"Everyone was instantly obsessed with it, probably because one semi-rural, teen-angst-against-an-idyllic-backdrop high school is pretty much the same as another.

"Not to mention the fact that the characters wore the same damn American Eagle clothes my entire school was born in."

Now Dawson's and Buffy are finishing their final seasons and many feel it's about time -- and not just because the stories have become repetitive, ridiculous or just plain dumb.

For some, it's come as quite a shock that the years have gone by so quickly.

"Just thinking about how all the characters on both shows are still in college and I'm five years out now and still watching, makes me feel old," says Christine Yi, 26, a Manhattan corporate licensing exec.