Note that
1) We saw Rose's body very much alive and kicking when she started her narrative of the penultimate episode. She's remembering and looking back, but she hasn't lost her body or become unrecognisably unhuman.
2) "Dying" of self is a very common metaphor to describe the loss of a loved one. "This is where I died" and "This is where it all changed forever" may imply that Rose is one way or another dumped by the Doctor - perhaps accidentally, perhaps deliberately. She stated herself that she had been wrong thinking that she would stay forever with him.

I have rumours of my own I want to share:

Alternate Pete Tyler goes to live with Jackie Tyler in her apartment. Rose gets in the TARDIS as the doctor fights of the cybermen and daleks. Rose passes out in the TARDIS. The doctor gets away and takes Rose to her mums apartment. When rose wakes up, Jackie and Pete tell her the doctor has gone, and he couldn't look after her any more. She runs to the window as the TARDIS leaves....

I think the whole world dies except for her ( cuz shes in the tardis) and she has too travel the world alone , getting free mcdonalds, and stealing stuff! But then she realises theres no men ! Uh-oh! so by the end of the episode shes killed herself.... THE END!!

insnt it obvious! she gets turned into a dalek or a cyberman! thats how shes still talking!

dont be silly paddy! hello ! she cant get FREE MACDONALDS if shes a dalek! she wont have hands ! so dumb............. p.s GO MACDONALDS!!

If she was a Cyberman/Dalek then she wouldn't be talking like a real person, would she? New theory: She does die, but the Doctor can go to places all through time and see her, can't he? Maybe even before she met Doctor No. 9...

She doesn't die, because at the start of Army Of Ghosts, that's her talking now.

Well we were al rong! she died in her other world! shes now living out her life in the parrallel earth !! boo hoo no FREE MCDONLADS!! but i cant wait to see catherine tate in the christmas eppy!!!!