There is a lot of difference between Anandi's relationship with J's parents and Nimboli's relationship with Kundan's parents . This is the deciding factor about the durability of the kacche umar ki pakke rishte . Sumi and Bhairon encouraged Anandi to develop the bond between Anandi and Jagya.
Anandi who looked up to Sumi like a mother just followed Sumi's directions and forged a bond with Jagya . Jagya saw the advantages like having someone do his homework while he went out to play was the deciding factor for J.
Well Dsa and Anandi was a battle of egos and ideology which Anandi won finally after paying a price.
Kundan's parents actively discourage any bonds that are being formed and neither Nimboli is interested or ready to forge a bond with Kundan. Nimboli doesn't consider Kundan's parents as her parents like Anandi did . She is just putting up with them as part of her fate/life.
Kundan wants something from her and he is getting opportunities to win her trust and respect but the bond whether it becomes deeper or not depends on whether he can earn her trust and respect or not.
Jagya earned her trust got what he wanted then broke her trust thus lost his place in her heart and life for ever but his family earned her trust and respect and permanent place in her life by giving her what she lost.
So there are a lot of differences between Anandi's childhood sasural and Nimboli's sasural.
Kacchi umar ki pakke rishte that formed in her life is because of the oppressive atmosphere and the atrocities the three Kamili Mangala and Nimboli suffered so far . This bond is more like a bond which prisoners share with each other . Take them out of that place and transport them to a better place these bonds between the three won't be so strong.
Kamili's bond with Pushkar will become stronger.Provide Mangala a purpose in life other than Nimboli get Nimboli into school the bonds will become weaker dependence won't be there though the affection remains.
It is easy to get her to break her away from Kundan and his parents.