Diaz, who dated Timberlake from 2003 to 2006 and starred with him in the 2011 film "Bad Teacher", said in an interview she will always love him in different ways, reported Showbizspy.
"Jessica has always been threatened by Cameron's close relationship with Justin. And she believed Cameron was saying that if Justin was having second thoughts about the wedding, she would be waiting for him with open arms," a source said.
"Jessica was deeply concerned that Justin could be getting cold feet about marriage. She basically told him that if he didn't cut contact with Cameron, he could forget about marrying her," added the source.
Timberlake proposed to Biel in December and the wedding will reportedly take place this year.
"The wedding is on and imminent. But Cameron's interview really threw Jessica for a loop. It has her questioning Justin's trust and commitment right down to the wire," said the source.