From Devika's POV , I think she was completely taken aback when she saw Ravi taking such a drastic step of sitting in the mandap and marrying her without bothering to inform her .. for her that was unlike Ravi since so far he did everything keeping her in confidence ... this is where the seed of doubt was planted in Devika's mind ..
The doubt turned into full fledged Misunderstanding when she overhears Manju's rant to Ravi
Also she told Ravi during their SR that your first plan was to marry Nivi and so u proposed her but when she rejected it , u trapped me ... so I guess this is where CVs explained why Devika thinks Ravi married her and not Nivi instead ... I know Sakshi told Devika that the proposal was for her and not Nivi and even Devika believed it that time but post this marriage , I guess she now believes Ravi even took Sakshi for a ride to marry her
I know Devika is stupid in this case but if we put ourselves in her place , we might b reacting in same way like Devika .. imagine my best friend swaps the dulha and gets married to me without telling me 😆 .. we too will hv 100s of doubts in our mind ... Here we know why Ravi did what he did as we hv seen it all but Devika has not seen anything that Ravi went through before marriage , so for her Ravi overnight swapping himself with the dulha without informing was a big jolt and so henceforth she is believing anything thats said against Ravi ...
I sort of feel bad for both .. hope Ambe Maa does some miracle and clears this MU soon .. in this