"Marriage offers stability, and maybe that's why nearly 7,000 couples a week begin new family lives of their own,” she said.
"Sadly, for many of these marriages, reality fails to live up to expectations."
While the comment may have been missed at the time as Charles and Diana made strained attempts to continue the illusion of wedded bliss, looking back the words could be seen as an ominous warning of things to come.
The royal couple ultimately announced their split in 1992 – and divorced in 1996 – after rumours of infidelity plagued their relationship.
In 1992, it was publicly revealed that Charles and his former girlfriend Camilla Parker-Bowles had been engaged in an affair for years.
Diana herself has infamously weighed in on how Camilla contributed to the breakdown of her marriage to Charles during an interview with BBC Panorama in 1995.
When asked by Martin Bashir if Camilla was a factor in the couple’s split, Diana replied, “Well, there were three of us in this marriage so it was a bit crowded.”
The words are a far cry from what she uttered in a joint TV interview with Charles early in their marriage in 1985, where she played the role of doting wife.
"I think my role is supporting my husband whenever I can. Always being behind him, and being encouraging,” she said.
"And most importantly being a mother and a wife. That's what I try to achieve. Whether I do is another thing, but I do try."