The presenter had spent six weeks away from Luke Worrall because of work commitments, but missed him so much she arranged a secret trip to the English capital to spend some time with him.
She explained: "I hadn't seen him for six weeks because he's been working in the UK and I've been working in Los Angeles. His agent told him to go to a hotel for a modelling job, but when he got there I opened the door - he was shocked!"
Luke managed to take a break from working while Kelly was with him, and the couple have been enjoying having the time to go to their favourite hang-outs in the city.
Kelly added in her column for Closer magazine: "Being back to together is amazing no matter what we're doing, whether it's going out or staying in. We've been going out to all our favourite restaurants and the places we used to go when we both lived in London. I love everything about the city."
Kelly revealed last week she has broken her elbow trying to stop her mother Sharon Osbourne's dogs from fighting, and she says the injury is still causing her discomfort.
She said: "My sister Aimee's dogs started a fight with some of my mum's dogs and as I was running towards them to break it up, I smashed my elbow against a wall. It was the worst pain I've ever felt, so I went to hospital to have it looked at.
"The first set of X -rays didn't show much, but they re-scanned my arm and it turns out I've fractured a bone, so I have to wear a sling for the next few weeks. It's such a pain."