“Rachel is very outgoing and her friends are very important to her,” says the source. “Hayden is the opposite. He can be very antisocial.”
On Wednesday, reports surfaced that Bilson and Christensen were calling it quits after nearly 10 years together and had separated about two weeks ago.
The pair, who met on the set of their 2008 film Jumper and are parents to 2½-year-old daughter Briar Rose, have had a series of ups and downs in their time together. They were first engaged in 2008, but called off their engagement in August 2010. They would end up reconciling just three months later.
Part of the problem, according to the source, was Christensen’s intensely private nature. “Hayden never wanted to join her for special occasions, like weddings,” the source explains. “Rachel had to attend by herself. Her friends thought she could do better.”
The 36-year-old Hart of Dixie star was spotted out for the first time since their split on Wednesday, shopping at Sweet Williams children’s clothing store.
Though the two were notoriously private, Bilson opened up about their relationship in a 2013 interview with Cosmopolitan.
“I’m a really good girlfriend — I always put all that first in my life. I’m definitely the person who would make him his favorite dinner to come home to,” Bilson said at the time. “I love to cook, so we make dinner at home a lot and watch movies.”
Most recently, she posted a photo of him on Instagram in April, wishing Christensen, “Happy Birthday Handsome.”
In 2015, he opened about naming their daughter Briar Rose.
“There’s a Disney reference there I suppose,” he said of her uncommon name. “The original Sleeping Beauty is called Briar Rose. Rachel — we both love Disney — but Rachel especially was very keen on the name.”
Their camps have not responded to requests for comment.
This article originally appeared on PEOPLE.