Cavallari's representative subsequently confirmed the couple has ended their relationship.
"Kristin Cavallari and Jay Cutler have ended their relationship," her rep toldLife & Style on Monday. "This is a difficult time for them, and they ask you to respect their privacy during this time."
Cavallari is "in shock" about her split with the 28-year-old NFL quarterback, according to the People source.
"She was planning her dream wedding, the date was set, the location -- everything was set," the source added. "She's in shock that the dream wedding she was planning is going to end this way."
Although the reality TV star is apparently crushed over Cutler's decision, she seemingly hasn't been trying to keep the news under wraps. She joined her friends at a Los Angeles lounge this past weekend and was spotted without her engagement ring.
"She was hanging out at a table with Nicky Hilton and Alessandra Ambrosio," another source told People. "She was telling friends how they called off the engagement."
The announcement of the couple's wedding cancellation came just a week after reports that Cavallari and Cutler had posted wedding registries surfaced.
Cutler and Cavallari -- who also appeared on Laguna Beach, MTV'sThe Hills predecessor, while she was in high school -- got engaged in April when Cutler proposed during a spontaneous vacation to Cabo San Lucas.
The couple began dating last August after they met through Giuliana & Bill star and E! News host Giuliana Rancic.
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