Epic love story where the couple is fated to be together

Just finished watching Someday or One Day and the OTP went through hell to be together. The drama proved that love transcends time. It was so pure and heartwarming. 

I think the OTP beat my all-time favorite couple from Crash Landing on You, which is another epic love story where the couple is destined to meet and fall in love. They literally overcame death and political barriers. 

Any other dramas with epic love stories like these two? I'm not talking about the typical childhood connection/fate drama trope (unless it plays a HUGE part in the plot). I would also prefer if there's no love triangle. I want the main couple to only have eyes for each other :)

Here is literally what you're searching for - a destiny binding the couple through lives, time periods, all the stuff to overcome including the bad fate itself. They all overcome this bad fate and make it right.

The Legend of the Blue Sea (2016)
The King: Eternal Monarch (2020)
ReLIFE (2017)

I love this topic. I love to think of these kind of couples as soulmates. I have some in mind that I think will fit right in with your demands (of course you've watched many of those I wanted to recommend so the list isn't that long): 

1.  Iljimae - their story really seemed fated at the time.  They go thorough a lot together but  overall is really beautiful and deep.
2.  That Winter, The Wind Blows - star crossed lovers at its best. One of the best melos I have watched! Their romance really is EPIC.
3.  The Princess's Man - one of my all time favorite love stories. The chemistry between the leads is out of this world. The story is very compelling and the scenes they have together always make you feel all kind of different and conflicted emotions.