I think Neelam track was finished !! But According to ur view...if thats the case yash would definetly let neelam to marry the groom and wish her all the happiness she would get with his hubby ever after...!! Yash was basically kind at heart...he'll not let his beloved ones to suffer( here Neelam as a sister) though it was practically merged or similar with his own life...!! He cares more for others rather than his life and happiness !!