How do you write a good Romantic drama?

The classic romance is a hero's quest. The Iliad is about the love affair between Paris and the married Queen Helen. It was heroic of them to elope because they ignored the danger. Agamemnon launched a war to get her back, another romantic quest. Romeo and Juliet is so classic it has spawned many retakes of the same story in modern form.
The musical West Side Story is one take. I assume you want a simpler story, so why not talk about how Judy is madly in love with Antonio who won't give her the time of day but who can't get the attentions of Isabella? Lots of fodder for dashed hopes in a story like that.

fallow???

*writer's

You're staring at the big picture. Start small, then build.
Answer these questions..

Who? - Create one character boy/girl/alien/robot etc..
What? - What are they doing? Are they a student? Boxer? Racer? etc
Where? - Where does the story take place? School, another planet, an office? etc
When? - Summer? 10 years ago? 100 years from now? etc
Why? - Why are they doing what they're doing? Stress, Revenge? Fear, love etc...

Smart small then build...that's how stories get written.