I would be probably extremely scared of her letting herself go to her emotions and turning away from the light that shines in her heart. Letting all the wounds bleed and the pain gets to her, eventually changing her.
I fear something bad would happen to her, something physically bad, on this one. I've already suffered watching her dying and gladly that wasn't "real", so if It just did I would just lose my mind about it I am pretty sure I am the kind of person to completely go borderline if I'd feel like she'd be in danger. In the lights of the awareness I have today I'm afraid this could cause a lot of problems in our relationship.
I think it wouldn't be fair just me considering what I might fear, and just not thinking about what she might fear, could it be things about me, or things happening to me. As I mentioned just upper, I think she'd be scared of me losing my mind over her and doing something regretful.
Given my will to protect her at all costs, be it physically and emotionally, I think she'd be worried about my health. This could end up being a bother to her and my presence weighing down on her.
Fear is a restraint. Essentially, we need to get paste it, at all costs. Making a clear distinction between fear and willing to take your time to take a decision is also a good thing. Eventually, we need to remember than, in order for good things to happen, we need to look on the bright side of life, and never let the light inside us stops shining, so ultimately, we can hand it over and together shine like a billion stars.