There are reports that Prince William told his grandparents, Queen Elizabeth II and Prince Philip that he wasn't sure if he loved Kate.
WATCH: Prince William regretted break up with Kate Middleton, expert reveals
Prince William and Kate broke up briefly in April, 2007 despite rumors that he would propose that year.
The internal issues may have been there all along, with William reportedly saying he felt the relationship was "claustrophobic."
They were quickly reunited in July that same year, but reports of a secondary reason for their breakup have been unearthed.
Royal correspondent Camilla Tominey revealed that Prince William wasn't certain of his love for Kate Middleton.
“After they split up, William confided to his grandparents that he was not sure if he loved Kate enough.
“Now they are back together, the Queen wants William to do the right thing – either marry the girl or let her go.
"She would rather they broke up for good now than get married only to have it end in divorce if five years’ time.
“But if Kate is the one, then a five-year courtship is long enough.
“Prince Philip has told William he cannot keep stringing along Kate for ever."
The break was enough to convince Prince William to propose to Kate Middleton, but there is no denying their rocky beginnings.