115 hours, end of main game and still can't romance Sera

From the literal beginning of the game, I have done Every flirt and romance option for ONLY Sera, I have chosen Every positive approval option so that my approval has been maxed many, many, many hours ago, I chose all the correct options such as mythral being a complete lie, I chose I am interested in you, I have had cookies on the roof; I am so far into the game that I am about to have gotten someone special back for Morrigan (refraining from spoilers) and have to fight a big big big baddie next and yet Sera still will not romance me. I am not in a romance with Anyone else at all, haven't even flirted with anyone else. No mods either. I followed all of the guides to a T and nothing worked. And yes, I have made certain that I went through every dialogue option other than kicking her out of the whole inquistion. I went through all of this because I really like her character and wanted to see the how the romance would blossom only to have Nothing happen. She just stands in her room in skyhold spouting warm greetings and watching the sunset with me and talking about my compatriots but that's it. No hat quest or any follow up no matter where I go. And I take her on All of my quests all the time. She's been everywhere with me. She's not saying let's travel around more. I don't know what to do but after this many hours, this is really aggravating.