Just because Caroline and Lindon were only first photographed
together in 1992 does not preclude their involvement before that.
I distinctly remember reading about Vincent Lindon spending lots of time with the widow Caroline and her children in Provence only a few months after Stefano's death...in both the French, American and British gossip press. This was in the spring and summer of 1991. As Florestane
has pointed out, Caroline was a very passionate young woman..in love with love apparently. Up until her marriage with Ernst-August, she was always
linked romantically with a man since her late teens, always. She has changed and mellowed a great deal from those days.
I have always suspected that at least part of the reason she decamped to Provence from Monaco so soon after Stefano died was to grieve in peace...and to carry on with her private life away from gossip and prying eyes in Monaco.
For the record I do believe Caroline and Stefano loved one another but I have read enough about how they got together and Stefano's background to believe that it was not
a fairy tale perfect marriage.