According to Disney’s D23 Magazine, Thor: Love and Thunder will include a series of flashbacks that will shed light on Thor and Jane’s relationship including its ultimate demise.
The exact reason for Thor and Jane Foster’s breakup is not yet revealed in MCU. The reference to their spilt was hinted at Thor: Ragnarok, Jane’s love interest in Thor becomes less in Thor: The Dark World. Jane’s decision was supposed to move further with her research. After 8 years Thor and Jane were reunited in Love and Thunder. Thor just counted the days without Jane from the breakup day.
Thor: Love and Thunder synopsis follows, “Thor finds a quest for inner peace. But his retirement is interrupted by a galactic killer known as Gorr the God Butcher, who seeks the extinction of the gods. To combat the threat, Thor enlists the help of King Valkyrie, Korg, and ex-girlfriend Jane Foster, who — to Thor’s surprise — inexplicably wields his magical hammer, Mjølnir, as the Mighty Thor. Together, they embark upon a harrowing cosmic adventure to uncover the mystery of the God Butcher’s vengeance and stop him before it’s too late.”
Taika Waititi is directing the film, the cast includes Chris Hemsworth as Thor, Christian Bale as Gorr the God Butcher, Tessa Thompson as Brunnhilde/King Valkyrie, Jaimie Alexander as Sif, Taika Waititi as Korg, with Russell Crowe as Zeus, and Natalie Portman as Jane Foster/Mighty Thor.
Thor: Love and Thunder will hit theaters on July 8, 2022.