Hello! Sorry in advance that is vague - this was a historical drama that my friends were watching and I would randomly see scenes of and wanted to know if you guys knew the title of it...

The main thing I remember about this drama was that the King loved only his queen and would refused any concubines. At one point in the drama the queen even tried to find concubines for the king but he adamantly told her only loved her. Somehow later in the series a lady shows up and tried to seduce the king; she uses a (herbal) candle that somehow makes her more attractive?? to him & the Queen finds out that he was unfaithful and is heartbroken since he told her over and over he only loved her & it was known in the palace that the King would never marry anyone else  

Again sorry this is vague - it's been a minute since I had seen scenes of this show &  I'm even questioning my own memory... 

 the only other details that I can remember (Hopefully I'm not combining 2 dramas in my head):

- this was a LONG drama (like every Cdrama) & the show actually wasn't super focused on them in the beginning  since there was at least 2-3 other couples in the show

- their relationship had always been stable and they rose in ranks together (at this point I MIGHT be mixing dramas LOL) I know the king was good at martial arts and she might also have been ??

I don't think it was a fantasy historical but again I might be mixing up dramas at this point

  Thanks in advance! 

Until the first para, it reminds me of 'The Crowned Clown' but other things doesn't match with it and it's not a Chinese drama

I found it!! Queen Dugu! :D 

it sounds like legend of lu zhen