Let's have a healthy debate...

Well to be really very frank... i guess its both of them...

At times when someone is so very much hurt as much as RK was for his faith in Bappa and realizing that his very friend was not by his side in times of his trouble, he starts shutting himself from that person or thing (in this case it was Bappa for RK) ... And as we already saw he was in total denial that he still harbored any feelings for his friend his Bappa here...

At such times you just need a nudge or a push to get you out of that phase of denial... You need someone to be point blank and tell you things you don't wish to hear... Like his apprehensions when he saw the jyot being put off and tried covering it or his act of the veg seekh kabab... He just has to be shown a mirror to his true feelings and thats what Madhu did ... She just made him realize that how much ever hard he tries he can never separate himself out or away from Bappa... That what has triggered RK's thoughts again to come out of the denial state that he lived in... His confrontation with Bappa's murti very much proves that what he is so hurt about and why he was so hurt... what he expected out of his Bappa and why he was so disappointed...

But yes coming out of that phase... its his own thought... his own beliefs and his own realization about his faith in the divine deity

So as much as Madhu is responsible for the nudge or the push to RK... its RK's own beleifs that helps him here...