So I played DA: O a bit ago and noticed something. As part of her starting equipment she has a "Seeker's amulet."
At the end of DA2 we notice her in Seeker Armor with Cassandra, but it appears she's been a Seeker since DA:O.
It seems that Leliana wasn't in Lothering simply to hide out from her past. She was there for a reason, and that reason led her to join the Grey Warden. Her whole character was an act to get her closer to him. What if the problems of DA3 were already anticipated and she was sent to find the Grey Warden...