The pair, who finalized their divorce in April, met back in 1995, months following her split from No Doubt member Tony Kanal. (She said that she would have married Kanal, 45, and was "obsessed with him" even after he pulled the plug.) At the time, Rossdale, now 50, invited Stefani to KROQ's annual Almost Acoustic Christmas concert in Los Angeles.
"I had basically gone to the show with Tony for the second night because we weren't playing that night. I think Gavin had requested I come or something like that. We already knew we were going on tour with his band [Bush]," Stefani, 46, explained to Stern, 62.
"When I met him and looked up at him, I was like, 'Whoa.' It was different. I was in quite a rebellious place because I was feeling really rejected.…Somehow he got my phone number, and that was that. He stalked me, I think," she added. "I was only 26, and I only had the one relationship. I still lived at home when I met Gavin."
The pair eventually got together a few weeks into their tour. They married seven years later in 2002 and are parents of sons Kingston, 10, Zuma, 7, and Apollo, 2. (Stefani appeared embarrassed when Stern said that Kanal was the only person she ever slept with before Rossdale.)
Stefani and Rossdale's fairy tale came to a screeching halt, however, when they announced their split in August 2015. Three months later, Us Weekly exclusively revealed that Rossdale, 50, had been cheating on the "Misery" singer with their children's nanny Mindy Mann.
"Its been an unbelievable journey. You can't even imagine. It did rock [my world]. My parents were totally helping me through the whole thing," Stefani said of the split. "I was in a panic. I was in hell."
She adding, tearing up: "I think, for me, I feel like I always wondered, Why did I get so unlucky in love? I have so much love in me. [Howard] you are making me cry."
Of course, as fans well know, Stefani did find love again. She's been dating fellow Voice coach Blake Shelton since November 2015. The pair leaned on each other following their respective splits. Shelton ended his four-year marriage to Miranda Lambert in July 2015. "It was an incredible gift to be able to have a friend," she told Stern.
Can't get enough of Us? Sign up now for the Us Weekly newsletter packed with the latest celeb news, hot pics and more!