Why Vasu can't understand Sadhana ?

I really dont get why Vasu can't understand Sadhana ? As far as we know both Vasu and Ambika were not from really rich family and may have seen same issues as Sad and Ragini. Also there is no foundation to Vasu's fears that Sadhana would try to control as sadhana has never spoken a word against Vasu ever.

I think she is just jealous of sadhna, because every one loves her.... and it seems so natural, without playing any tricks.... so vasu sees it and feels unconfortable, both her sons blindly follow sadhna and utterly wish to please her, even her husband inderjeet....

Sadhna deserved what she got from Vasu. Vasu hatred towards Sadhna is acceptable.

Sadhna knew that Vasu loves her sons a lot. And she can ignore her status and society for them. She can leave them just for her sons. She proved that by RaGvir marriage. Where her friend insulted Ragini and her status but she didnt care...