For many of their nearly 10 years as romantic partners, Irina Bolgar said, she and Pavel Durov enjoyed a luxurious lifestyle. The extravagance grew as Telegram, the messaging app Durov created, became a worldwide hit and cemented him as a billionaire and one of the world’s most powerful tech executives.

During the summers, they would spend about $US1 million ($1.5 million) for a month at a 116-acre resort (about 47 hectares) in Sardinia. In Dubai, United Arab Emirates, they stayed in a beachside penthouse with its own elevator. Private planes ferried them to Paris, Italy and Monaco.