The former TOWIE star made the romance official by describing Louis as her "boyfriend" in a message posted to Instagram this afternoon.
Referring to the New Year's Eve bash at Louis' house, she said: "Only just starting to feel normal again!! My boyfriend knows how to throw a good party!!"
Fans were quick to share their happiness at Lucy's big news, with one saying: "OMG Lucy, so happy for you! You deserve this!"
Another said: "You guys look so cute!"
Lucy and Louis became friends while appearing together on BBC One show Tumble last year, but sparked romance rumours in December thanks to some cosy selfies and pictures of them out and about in Essex.
And now we know it's true!
Alongside her 'boyfriend' quote, fitness fanatic Lucy posted a quartet of photos including one of her and Louis kissing.
The party at Louis' home was a tropical-themed bash complete with palm trees, flower garlands and an amazing looking ice contraption for taking vodka shots… maybe not so tropical but still fun!
Lucy was previously linked to TV presenter Gethin Jones and was previously in a long-term relationship with former TOWIE co-star Mario Falcone.
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