Short answer: Thor and Jane broke up, according to Marvel Studios head Kevin Feige while talking with Entertainment Weekly.
Here's Feige's full answer:
"We wanted Thor to encounter somebody that was near his equal and that his relationship with Jane may have evolved in unexpected ways in between The Dark World and Ragnarok and we wanted to pit him against a character who was much more his equal and in many ways his superior. Valkyrie is trying to not embrace any sort of Asgardian heritage that she has. Thor thinks maybe that will create a bond between them and, on the contrary, she wants to forget it all entirely.”
THOR: RAGNAROK releases in the U.S. on November 3.
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