As it stands right now, both you, and the unvaxed lady, are on a level playing field. Despite your jabs, you can still get C19 and pass it on, and so can she. There is no validity at all in, ' but the vaccinated won't get it so bad', how are you ever going to know if you've had it worse, or not so bad as anyone else. There's no score sheet with marks out of 10.
This is SO divisive. You liked working with the lady, you found her lovely, clever and charming, and now you are letting this 'fear' change the way you react to her, just because of her personal views.
That is grossly unfair of you, and you are actually discriminating against her.
Wear your mask, protect yourself if you feel more comfortable, you do you, and let her do her, and carry on your lovely working relationship. Don't forget she will remember this in time to come...... then you'll be the one feeling awkward.