The 33-year-old announced the news on her Instagram Stories during Q+A with her 868,000 followers.
WATCH: Dianne Buswell and Joe Sugg enjoy romantic Italian trip
Responding to a fan asking if she would be attending, the star penned: "Unfortunately not but I wish them both so much happiness and I hope they are having the best time, I adore them both. @grazianodiprima @giada.lini."
The Strictly star added: "Also I got to see them this week," on a photo of the pair reuniting with fellow Strictly pros.
The star took to her Instagram
Earlier this month, Dianne had fans obsessed over her fabulous holiday photos alongside YouTuber boyfriend Joe Sugg as the pair jetted off to Italy for a romantic summer break.
The duo put on a radiant display as they shared a selection of loved up selfies which showcased a variety of memorable moments including a dreamy evening stroll, a relaxing boat trip, and an adventurous day trip.
Captioning the post, Dianne penned: "She captioned the post: "The Selfies of Italy #thesquad #italy."
The pair are so loved up
Fans were all thinking the same things and replied to the stunning montage with similar observations. "All it takes Mr Sugg is one knee and a ring. You both are meant to be together."
A second added: "Wedding bells????? You two are soulmates."
Another added: "When are these two lovebirds going to get married. They are so perfect together and I love to see them married soon and having children."
Dianne and Joe met on Strictly
A fourth agreed, writing: "Your love story makes me so happy for you both (I know I don’t know you but nice to see people happy!)."
A fifth said: "Love this couple followed them from Strictly perfect match," with two red love hearts.
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