I won't be able to pinpoint the exact similarities or differences, unless I see the movies.
SDR had an interesting concept. A lot of youth are indeed questioning the necessity of marriage. Many don't want to marry or end up marrying very late. The length of time from liking someone to being ready for a mature committed relationship is much longer. So a movie that reflects that was a good idea. However, the execution was completely flawed. It ended up making youth look stupid, impulsive, irrational and selfish and completely missed addressing the genuine doubts and fears of commitment in a decent manner.
HTP on the other hand looks a lot more like a rom com. I don't think it is trying to portray the doubts and fears of commitment young people face. I think the focus is more on the free spirited nature of one person. The story seems to be more of an unlikely friendship between two polar opposites that blossoms awkwardly into love. Also Parineeti's character doesn't seem to be one of doubts over commitment, but more of wild spirit that doesn't want to be tamed. I think that's a big difference.
Anupamaa
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