Pippa Middleton and her longtime boyfriend Nico Jackson have split after more than three years together.

“It was mostly due to geographical issues. They were rarely together since his move [to Switzerland] and it just caused too much strain on their relationship. They still love and respect each other,” a source told Us Weekly.

pippa middleton and nico jackson

Pippa and Nico in September 2014.

Pippa, 32, and Nico, 37, first started dating in 2012 after Kate Middleton‘s younger sister called it quits with her former flame Alex Loudon.

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The couple — who were previously rumored to have future plans to walk down the aisle — were last spotted together in public last month enjoying a PDA-filled date night in London. Just days later, Pippa was seen dining with ex-boyfriend Alex in Fulham, England.