The couple -- who have been dating since September after meeting on the set of Dark Tide -- have given one another keys to their respective apartments so they don’t have to spend any time apart.
A source told LOOK magazine: “These two are so in love, they want to spend as much time together as possible.
“They hate being apart, even for one night if they can help it. They want to be home together, as neither of them particularly likes meeting in hotels.”
Olivier is currently living in Halle’s secluded Beverly Hills mansion, but the actress -- who has a two-year-old daughter Nahla with ex-boyfriend Gabriel Aubry -- is keen to spend more time in her lover’s native France.
The source added: “Since they both need to be in Hollywood for work, it made sense for Olivier to move in sooner rather than later. And they love the privacy of her place, although Halle says she can’t wait to get to know Paris better. They are definitely not taking things slowly.”
See more Halle Berry and Olivier Martinez pictures (click any photo):