I don't agree that Vaishali is nt a good mom.... In the starting we did see that Vaishali did understand his plight and talked to him abt his actions.... The reason y she did nt support Dev at that time was only b'coz his marriage was complete, u cudn't leave a person on the very next day of the marriage stating that it was a misunderstanding and so they will break...She forbade him to tell anything to anyone was only due to Dadi's and his father's ill-health. She knew wat havoc it cud have brought dwn in their family once when the truth wud be out and wat Dev's intentions were...
She did try and comfort a stubborn Dev (at that moment) and explain him things without revealing her own grief to him (remember she was so close to disclosing the truth to him wen Dev made a desicion to leave to America forever, she had also grasped the reason behind his desicion),so strong was their relationship.
Secondly, after the death of her husband, Dev also got some grip over himself and started trying to woo Vishakha (which was done in open--like asking her for a movie, lanning for farmhouse,etc)..Ths attempts of his gave Vaishali a sense of satisfaction that Dev had over-grown his grief and was nw accepting this relationship...
Earlier to all this she used to explain Dev bt after this attempts when Visakha proved herself unworthy in the responsibilities and she saw her son's sad stricken face, she did nt give any lectures to Dev this time but tried to tallk things with Visakha as she felt that that Dev was sad as his wife was nt able to fulfill the responsibiites due to which he had to hear many commments from Mrin and co.
As per Dadi making decisions of the household is very natural in the joint family... An elder person who is wise and keeps the whole family into one is the one who has the last word... When her son was alive it was he who held on to the reins bt Dadi's wishes and desicions were never overlooked..bt after his death dadi had to take on the responsibilty b'coz Dev has just started his journey as Raj Purohit and Susheel wud easily manipulate him off...
Yeah i was pretty surprised today that before accepting the proposal she did nt ask Dev abt his wishes and his DG..bt maybe b'coz she thinks that its a closed chapter and its nt required to again dig into his pain.. which he wud have forgotten