Biwi is doing all this for him only na...he was not happy and in upcoming bts too we can see that he also was trying everything to bring Tanvi and make her do some rasam...i know Mauli accepting this is her stupidity bt she is doing all this for Rahul so that he can be happy on his wedding...just like Rahul married Rati so that he can get divorcee tag..this shows both Rahul and Mauli can go to any extent when it comes to happiness of other one and they often take wrong decision
I know and I respect and admire her for that but it doesn't mean she will pacify every whim of DW and inflate her ego more and more.Agar shart rakhna hi tha toh Rahul ke saamne kyu nahi rakha woh toh uska beta hai na... isiliye nahi rakha kyunki Rahul bother hi na hota ye sab se ulta 4 baatein aur suna deta.Mauli toh bholi hai Rahul ka use karke agar shart rakhi toh maan legi that was her point in this particular scene.
Sometimes she just needs to stand her ground especially in absence of Rahul har baar Rahul nahi hoga support karne ke liye kuch ladayi akele bhi ladni padti hai.She needs to understand one can not please everyone agar poori family aise behave karti toh case alag tha par yah toh yeh akeli DW zidd karke baithi hai toh Mauli ko bhi presence of mind dikhana chahiye tha ki nahi.Aur DW thi bhi chalak sabke saamne yeh sab nahi bola....bola toh akele mein hi bola parlour mein and pakka she will probably tell Mauli not to tell about this to anyone.
Maybe one can argue she felt the need to please DW more after seeing Rahul being hurt and vulnerable in the clinic mentioning about his mother but she could have been smart about it.