If Sadhana had not married Alekh then RagVir would have not met each other so easily. Its as simple as that. Sadhana would not have married Alekh if Vasu had not agreed for RagVir alliance. So it was Sadi's destiny to marry Alekh and she was a mean to bring RagVir together.
Sadi's sacrifices didn't go waste as RagVir fell in love on their own. Sadi has a pure soul, so she could feel that RagVir were made for each other after thier first meeting. "Issme Rab ki marzi thi".
Ranveer would not have even considered marrying Ragini in normal circumstances. Ragini had color complex issues and Ranveer wanted a fair girl. Their families have different values and status. But they were meant to be together, so they got to know each other first over the phone. Ranveer fell in love with Anamika who had similar good qualities like his Bhabhi. Thats how he used to describe her to Sadhana. So Sadi did play a big role in it.
I am sorry anu, but i really think even if Sadhna didn't get married to Aalekh, RagVir would met even then...its not cuz of SaAlekh getting married to each other, that RagVir started talking to each other, they didn't start loving each other as Ranvir Ragini, but they started loving each other as Anmol Anamika, and to be very frank Sadhna didn't have any role in it. Ranvir loved Anamika for what she was, her baatein, her nature, her thoughts all these made him fall in love with her so where on earth did Sadhna play an important role here??? Did Sadhna teach Ragini what to say and what not say or did she tell Ranvir to love someone because she had a good nature... RagVir themselves fell in love with each other and NO ONE, no one made them fall in love with each other, other than themselves, and if we say that Sadhna helped them in realizing their love for each other, then we should thank Aalekh, Indo and the old couples as well, cuz they were the main people who made Ranvir realize his love for Ragini and that was why Ranvir returned back from the airport.
I agree Sadhna sacrificed for getting RagVir married to each other, and she being the pure soul, understood that Ranvir and Ragini were made for each other, but is it really because of her sacrifice that RagVir are together??? i dont think so, even now no one knows about the deal that happened between Sadhna-Vasu, so the sacrifice made by Sadhna basically went in vain, cuz it was not because of her sacrifice that RagVir are together.
No one is denying that Sadhna played an important part in RagVir's love story, but she was surely NOT the reason why RagVir are together, Agar Sadhna na hoti toh there would have been someone else who might have helped them in realizing their love for each other. RagVir were DESTINED to be together, and agar Sadhna na bhi hoti toh bhi RagVir would have been together.