1. They can sit and talk about their past, why they both did what they did. Try to understand the reasons behind and try to learn something from it. Like saying probably atleast from this we should learn something and should not repeat these kind of things in future.
a) Ridz should understnad that she can't be too much self centered even if she was drowned in her own agonies. She should open her eyes out and atleast give some weightage to other human beings around her. I think she needs to say something in terms of being real sorry for having behaved that badly with Sid in the initial days.
b) Sid should make her understand that, "now on atleast you have to be more responsible for your actions. You were completely uncontrolalble (refering to the period pre marriage and post panchagani periods). I understnad that you were desperate etc but should know that there are other people (her parents) depending upon and should think about them also and control your feelings. We were all so much worried about. Love should make you strong, but unfortunately your love has made you weak. It has made you so weak that you did not know how to live on your own and needed someone else to take care of you." And he should finish by saying that "you should learn lot of things from past. You should never repeat those things again and learn to remain strong in any condition in future. You should be strong enough atleast to be self sufficient"
2) Sid is very sensitive towards Ridhima now. Every small deviation from what he plans for her, he is too afraid of the consequences. Recently when he fails to orgainize Ridz b'day suprise party, he thought his relation with Ridz will be crossed. It would be nice if they show that this kind of a too sensitive behaviour is because of going through uncertainity in his relation (regarding Ridz choice) for such a long time. Even after she made her choice, she is not openly expressing her feelings towards him. From what I see, she is not very expressive and is more of shy nature. But, she should be shown to slowly understand that lack of proper assurance from her is making Sid over sensitive. They both can be shown to make some efforts in improving thier comfort levels this way.
3) Then they can exploit the complicated nature of their relationship. She is a senior and he is junior, how they both cope up personally as well as professionally.
4) Then ofcourse, they have this Ridz- Shipa sister track
If they can't come up with any proper story line for the two, it would be best to close their chapter, pack them off to Houston. But I think dragging without any story is not good.
Probably you people can add more interesting and sensible new directions to this story.