Rattlehead, please go read the rule regarding the 3-foot lane. No batter is required to stay in the 3-foot lane. Ever. That lane only comes into play in specific instances, none of which are relevant here.
To answer the initial post, you have an interesting question. I suppose that once someone threw her a glove, when she began approaching the field with her glove, I'd assume she is a defensive player at that point, and has effectively abandoned her chance to go to 1st base.
But I have no rule to back this up.
