How I see it is she was basically gonna dump him the minute she came to know about the marriage and kid BUT they were still part of the show and like she said the proposal was so that 'the others wouldn't bash him' aka for the game. I'm gonna say this again, Rashmi is not what she's portraying on the show and in fact has a very headstrong and decisive outlook on things. Yes, she is image conscious.
How things played out after with Himanshi coming in and saying all that was the perfect time to have an outburst and finally declare that she no longer wants to be involved with him (with her bff by her side for added support).
So yeah. Everything is planned. 😆