i feel like communication was their biggest issue, like in many other couples. because of the traumatic sight she saw of harsen dragging his distant cousin’s dead body whilst she was pregnant, i don’t think she felt safe and comfortable enough to talk to him about her problems and the hard part about mental illness, especially depression, is that a lot of the time you don’t know why you feel the way that you do and it seems like that was the case for ercella. and after harsen returned, she didn’t feel valued as a duchess and he started seeing her less since he was busy. i feel like he should’ve reassured her and talked to her about his true feelings though i do understand he probably had a fear that she didn’t reciprocate the same feelings since she referred to him as her ‘best choice’. idk i just feel like they really just needed to sit down and have a real conversation about everything instead of expecting each other to be mindreaders😔