Nicole "Snooki" Polizzi, Jionni LaValle and their son Lorenzo
09/05/2012 at 11:00 AM EDT
For the past few summers, Nicole "Snooki" Polizzi relished going to the Jersey Shore while film crews captured her every salacious move.
But last summer, when the 4'9" reality star was entering her third trimester (she welcomed son Lorenzo Dominic with fiancé Jionni LaValle
on Aug. 26), everything felt different.
"It was definitely a little lonely," Polizzi, 24, reveals. "Everyone was still going out and staying up late and I just wanted to go to bed at 8 o'clock. I didn't want to do everything that everyone else was doing."
As she says in this week's cover story
, Polizzi became "a new person" after discovering she was pregnant with her son. "Everything changed," she reflects. "The partying is long gone."
And while Polizzi says she had the support of LaValle and her cast mates (especially Deena Cortese
and Jenni "JWOWW" Farley
), she's not sorry that this will be the last installment of the popular reality show.
"It's bittersweet," she says. "But my life has changed. I have a family now!"
The final season of Jersey Shore
premieres Oct. 4 at 10 p.m. ET.
For exclusive photos of Lorenzo –plus details about Polizzi's delivery, upcoming wedding, weight loss plan and life as a mom – pick up this week's issue of PEOPLE, on newsstands Friday