Rose can totally understand why the Doctor had to hook up with someone else. He needed someone. And she's not objecting. She understands that he felt lonely.
She knows there's been other people before her.
She thinks it's kind of sad that Martha is so obviously her opposite. A doctor and in with UNIT? Get real. That's nothing like her.
But when she has the Doctor, her very own Doctor, all hers, in her world now, she spends an evening looking up "Martha Jones" on the internet.
Apparently she died in the Cybermen thing.
Well. That solves that problem.
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