I want to watch a complicated love story. Generally I find this type of love story in Chinese historical dramas but I never got a full fledged story. The guy gets married to the girl as a political alliance and doesn't have interest to know her. And the girl is unwilling but gets married for her family and she has a liking for someone else. And some years pass like that and they live their life separately. Due to some incidents the guy starts noticing her and slowly gets interested in her. But when he gets to know about her liking for someone else he does not like it and the angst starts.

Pretty much it but in a rom-com format: Fated to Love You , Jealousy Incarnate 

Not exactly the same exact plot, but complicated:

Summer's Desire 

I Have a Lover this is one is the closest to what you're looking for

Que Sera Sera 

The Innocent Man 

When a Man's in Love