Wait, Back Up.
This is more of a drabble in script form than anything else but I rewatched JE and was struck by this plot piranha. (They are never,ever just bunnies.) I might polish this up later. If I got anything wrong I have a horrible memory.
DOCTOR: Rose, you've been in a parallel world. That world's running ahead of this universe. You've seen the future. What was it?
ROSE: It's the darkness.
DONNA: The stars were going out.
ROSE: One by one. We looked up at the sky and they were just dying. Basically, we've been building this, er, this travel machine, this, this er, dimension cannon, so I could. Well, so I could
DOCTOR: What?
ROSE: So I could come back. Shut up. Anyway, suddenly, it started to work and the dimensions started to collapse. Not just in our world, not just in yours, but the whole of reality. Even the Void was dead. Something is destroying everything.
[DOCTOR'S face goes slack. He then turns around to stare at ROSE.]
DOCTOR: What did I tell you to do? I told you that you can't go back. What do you do anyway? Build a dimension cannon and start punching though realities! Rose Tyler, how many universes did you pass through in your mad rush back to your doctor.
[DOCTOR is glaring at ROSE. ROSE is quivering slightly.]
ROSE: I'm not really sure, but I think it was over a hundred.
DONNA: Doctor, are you telling me that your girlfriend was so obsessed with you that she punched through realities without caring what could happen to the people living in them?
DOCTOR: Yes, she did. Now into the TARDIS. I'll deal with her after I deal with the Daleks. Also, I have to apologize to Martha Jones.
I added that part at the end because I feel that Martha got the short end of the staff.
Anyway,tenses. Rose says that she started using the dimension cannon before the stars started going out. She could have weaked the walls enough for her to pass though. Therefore, she could have weaker the Time Lock enough for DalekCann to get through. Therefore,its all her fault Donna died. Yes I know what happened but I still call it dieing.