There are a lot of hate on Rose for her being mentioned so much after series 2 and I honestly do not understand why it annoys people. If you know the Doctor well and watched the first two series of new Who then you shouldn't be so annoyed.
Lets look at the facts. The Doctor met Rose right after the Time War, where he literally lost his home and his people. Although he was a rebel he still was incredibly attached to his home and he lost it. He did not have any anchor left so he was filled with anger and guilt. The first person who actually got under his 'shield' was Rose. He was sad, nothing...
I know some of you can't see this on the actual BBC website, but if you live in the UK you can find this story here: link
No. 1, Gallows Gate Road. Part One. Written by Rupert Laight. Illustrations by Brian Williamson.
The first thing the Doctor heard when he woke was the sound of something tapping at a window.
He sat up in bed, ran a hand through his tangled hair and stared around him. Where am I, he thought. This isn't the TARDIS. It's a bed. A very uncomfortable bed. What am I doing in bed? I haven't got time for bed. This is madness.
The Doctor tested his memory. The last thing he remembered...
Before you ask, yes, I already know who Missy is. This is just two theories I have that involve her.
Theory 1: Gus and the Orient Express
I strongly believe that Missy was behind Gus and the events of the entire episode, "Mummy on the Orient Express".
1. Gus was an AI, as was Seb, Missy's receptionist that she most likely created.
2. Gus wanted to study the Foretold and reverse engineer the technology keeping it "alive". And this technology could very well be similar to what Missy used on her Cybermen army made out of corpses, much like the Foretold!