Ah! I apologize, I completely forgot the basics. Yes, I've treated her as best I can. Paid the merchant 1000 gold, plus spent 500 on mercs....I visit at the Keep at least once a week, also told her to close her door instead of peeping, etc. I do have the Amber mod, but I was checking Nalia's global every so often, and it was 1 until sometime after I left the Planar Sphere and had Lovetalk 25. My hunch is that I may have mis-read a conversation line or my mouse mis-clicked, thus pushing a bad line and breaking the romance, as everything was okey-dokey until I realized too late that the romance was dead and that I'd have to reload an ancient save and redo at least 3-4 hours of work to regain my current position.
Oh, and for mods...I'm running a Recommended BWP (v9? Was the latest version as of a few days ago) with a few minor adjustments, such as no TDD / SoS.