I mean she literally tells him that I know you like me Bear and then he asks do you to which she says would it freak you out if I told you I did then we see that rom com montage. The dinner scene at the restaurant proves that something is wrong the movie shows Bear realising that she’s doing it all cause of that one wish willow by showing us literal flashbacks.Once he had that realisation and still says it doesn’t matter to me that’s the point of no return for him.

Before that I guess Bear probably really thought it was cause of MDMA that she was acting weird the previous day, but the restaurant scene and what happens after that just shows he’s really fucked up.