I agree, it doesn't look like she left because of money. Plus, they are definitely going to reunite mother and son so her reasons wouldn't be that shallow.
Yeah, looks like Bua is either a widow or divorcee. Did they explain why she wasn't there for Shivansh's sangeet? Did he recently move in? The way they introduced Robin and Malati (?) I thought he was here for quite some time so technically Bua and Tanya should have been here and not in another city? I skipped plenty of scenes before their marriage so I'm not clear about it.
Bua and Tanya's flight was delayed. They even apologise to Shivansh.
And then both of them going off to bed like grumpy babies 
clown and evil. But her marrying Ronak is not gonna make any difference to PraShiv and this marriage. If Ronak marries Sonalika then there it creates a situation where PraShiv might come closer than ever. Shivansh’s career and business will get affected and he gonna be mean again and Bua Maa will will be Bua Maa. 

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