After 10 years together, country superstars Blake Shelton and Miranda Lambert are calling it quits. Subscribe now for an inside look into their shocking split, only in PEOPLE.
When Blake Shelton and Miranda Lambert announced they were divorcing after four years of marriage, friends of the former couple were saddened and shocked.
So why did their marriage – especially one that seemed to have all the makings of a lasting love story – come to an abrupt end?
Although Shelton filed for divorce on July 6 in Oklahoma, a friend of Lambert's says she had wanted time "to reflect" on the marriage, which their demanding schedules started to take a toll on.
"She wanted to try and make it work, maybe have more of a separation," her friend tells PEOPLE in this week's cover story. "But he said, 'I'm filing.' "
A source close to Shelton, 39, insists he had no choice. "It came on very quickly," the source says. "It was very clear that things weren't going to work out. So he decided to end it. He still loves her very much."
While the couple's marriage weathered its fair share of tabloid scrutiny over the years – including allegations of infidelity, which both always denied, and constant baby rumors – the Shelton source says the singer was completely dedicated to Lambert: "He hasn't cheated ever, ever, ever. This has really shaken him."
As for any tensions over starting a family, sources say that did not play any part in the divorce.
However, Lambert's friend says Shelton's rising star on NBC's hit singing competition, The Voice, did become a point of contention.
"He liked [being a celebrity], which isn't a negative thing, but it's just polar opposite to what she wants," the pal adds. "It was frustrating, and she didn't want to be part of that machine."
For now, Lambert, 31, has been touring – she recently broke down while singing her hit ballad, "The House That Built Me," at a concert in Wyoming – and Shelton is back in Los Angeles working on the ninth season of The Voice, where he has remained.
"No one suspected a thing," says a source. "He was the guy who was engaged and making people smile, which is what he does."
For more on why Shelton and Lambert decided to end their marriage, pick up the latest issue of PEOPLE, on newsstands Friday
Reporting by MELODY CHIU and MARY GREEN
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