YTA. You don't have a weird tense dynamic because of vanilla, you have it because after learning that your voluntary scent made someone sick, you just kept wearing it.

I have fragrance induced migraines. If a co-worker refused to be considerate about this, I'd be quite pissed. Bringing this up to people is very awkward for me because they think I'm telling then they stink or that I'm being overly sensitive. It isn't that they smell bad, it's that they make me feel like I've been punched in the head and like I'm going to vomit. I'm getting a letter from my neurologist to file with HR because I've even had people test me by hiding air fresheners to see if I would notice. I noticed. I missed a few days of work.

You're causing her physical discomfort because you want to smell a certain way. This is incredibly selfish. There are zero painful consequences to you. If you have chronically dry skin, use unscented lotion. Most quality dermatologist recommended lotions like CeRave are unscented and probably better for your skin than what you're using now, so it's not like you have to be leathery.

If I were in your shoes I'd apologize and stop wearing the lotion. You have no idea how many customers or less assertive coworkers you are bothering. I don't understand why you'd choose to continue to cause this woman discomfort.