I am sorry Diablo fandom, I was not familiar with your game, but now I know I am among friends
Lorath deserved love, Lorath craved love, Lorath hoped that love can fix him and make his trauma go away, he wanted stability and he wanted the safety of a home, which was ripped away from him. In "The Lost Horadrim" he has so much anger and he lashes out at those he loves, Tyrael and Donan.
Pairing him with a girl who is going through her own problems and does not have the patience and kindness that Tyrael and Donan have towards him, did both of them a disservice. If this was played as a absolutely unfitting romance, a literal one night stand that left both of them even more aware that they cannot have a normal life, I would be down for it. But this cannot be a genuine relationship, and I'd like to think the authors were not going for one.
Lorath is in love with the idea of an Adreona that can save him from himself, but that Adreona does not exist and they would both have to be different people for it to happen. That's the tragedy of it, that's how this story ends.
And if played straight this relationship is the worst of the 2000s/early 2010s hetero ships in action/adventure media, where the far more competent woman has to deal with a guy who she can barely stand, until he proves to her that he is better than she believed and she instantly rewards him with romance, a kiss or sex depending on the rating (you can see this in stuff like Eragon, How to Train Your Dragon, Wanted, Transformers, Ready Player One, etc).
That's why in order to fit in the gothic tragedy when it comes to Diablo, it has to not be a relationship or something you would ship.