The McFly drummer is currently starring on BBC One's Strictly Come Dancing and picked up the first 10 of the series for his waltz with partner Aliona Vilani.
Speaking to Fabulous magazine, the 25-year-old spoke about his relationship with the Escala violinist.
"She is the only girl in the world for me," he said. "I want marriage, kids, the whole deal."
Discussing his past fling with Lindsay Lohan, Judd recalled how "surreal" it was to have dated the actress.
"I had a fling with Lindsay... it was surreal, she introduced me as her boyfriend, then told me to kiss her," he said.
Meanwhile, discussing his Strictly Come Dancing rivals, Judd praised "hilarious" Nancy Dell'Olio for how she "sits and demands champagne".
Strictly Come Dancing continues tomorrow at 6.30pm on BBC One.
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