Board Thread:Skyrim/@comment-10207438-20130919024334/@comment-24400038-20140223230731

I thought of a way to get to the bottom of this. But I don't have PC

Tell Lydia you're parting ways, then spawn five stormcloaks and five Legion soldiers on top of her to create a brawl, and see if she'll jump in and help either side. (Make sure you're hidden so TLDB doesn't throw off the test)

Honestly, her NPC persona is probably closer to a generic Whiterun guard's. Neutral to both sides.