If you listen to Elsie's dialogue she mentions that in her time as well as others Erimis lives. This implies that either we never faced her in those timelines or we did and she killed us with stasis. Further supporting that she killed us is our funeral that we witnessed during season of dawn. For the 2nd part of my theory it's very clear that the darkness is interested in us since shadowkeep. Further more Elsie mentions that in her timeline we fell to darkness which suggests that if Erimis lives then the darkness resurrected us. Additionally Erimis's priestess talks about how the darkness can resurrect just like the light. Further more, this leads me to believe that our dark doppelganger which we met in the final cutscene at the end of shadowkeep, was actually us but from the dark timeline.