Don't Hesitate (2009)

These two series are very very much alike. From the best-friend steals boyfriend to many things that happen after that event.

This drama reminded of "smile you" the story was similar, they both are more family oriented dramas in both the female lead is heart broken because of a failed marriage.

Both, humble and naive(MFL)
devoted to family, 'friends' and first love.
betrayal, twisted revenge carry with support and backing from prominent figure.

I'm not saying that this is the same, I just thinks that if you take the insane people in this , well you can find their counterpart in don't hesitate, and it also carries that unconditional love kinda of scent.
Don't hesitate is about Soo Hyun a girl who makes the ultimate sacrifice for her first love, Min Young by donating her kidney to save his life. Then she gets betrayed. Her best friend, Sun Ah, seduces and steals Min Young away from her. Devastated by the betrayal, she meets Tae Woo,who is determined to not let anyone close to his heart.

both are Revenge-Dramas with more than 50 episodes. Both follow a woman who is somehow naive in the beginning and turns out to take revenge on the people who hurt her later. But in Heaven's Promise much more people die. Both worth watching it!

another good revenge drama and THIS IS PROBABLY THE BEST MELODRAMA I'VE EVER SEEN!