The lilac-haired television personality was rumoured to have got engaged to Matt before Christmas, but at the time she implied that the reports were false and tweeted: "Don't believe everything you read."
However during an appearance on daytime panel show The Talk yesterday (30 July), Kelly finally came clean and revealed that she and Matt have been engaged for six months.
Speaking about how she's been trying to maintain her privacy throughout the engagement, Kelly said: "People know we got engaged in December of last year, but kept it a secret for six months.
"I realised very quickly that in Hollywood people don't realise that you get married for love, they think you get married for attention and I don't want to do a reality show. I've already done that."
Kelly first found fame on her family's reality TV show, The Osbournes, and although she's used to being on camera, she has no intention of filming her own series with Matt.
"Like, every morning I wake up to another email and it's like: 'An offer you cannot refuse.' I'm like: 'I can refuse that. I don't want to be on another reality show, I'm fine right now. Thank you.'"
Coincidentally, Kelly's mum Sharon happens to be on of the hosts of The Talk and she was clearly beaming with pride while sat next to her daughter.
When Sharon's fellow co-hosts asked her how excited she was about Kelly's engagement, the opinionated X Factor judge admitted that there was only one thing on her mind now.
"I'm like: 'Yeah, more grandbabies!' Yeah!" she exclaimed, while Kelly shook her head in disbelief.
Even though Kelly might not have a bun in the oven just yet, she has recently been surrounded by other pregnant stars that may have given her baby fever.
Last weekend, the Fashion Police star attended her pal Fergie's baby shower at the SLS Hotel in LA and earlier this year, she also swung by Kim Kardashian's "Garden Goddesses" baby shower along with the entire Kardashian-Jenner clan.
Would you keep your engagement a secret? Let us know below, as the best comment from across the website each week wins £50!
More engaged stars in our gallery below