More than likely, her memories were starting to come back when Sylvia and Shaun became part of The Master race, unless The Doctor manages to get back in time to stop it from happening.
She first meets him in the 2006 Christmas special The Runaway Bride.
The following people/aliens returned. Sontarons Martha Daleks and Davros Rose Captain Jack Sarah Jane Smith Harriet Jones Mickey Rose went back the parallel world with a clone Doctor, Donna had her mind wiped after becoming part time lord.
In the original series, the Doctor gave TARDIS keys to Susan Foreman, Ian Chesterton, Barbara Wright, Jamie McCrimmon, Sarah Jane Smith, and Leela. In the 2005-present series, the Doctor has given TARDIS keys to Rose Tyler, Martha Jones, Donna Noble, Amy Pond, Rory Williams, and Clara Oswald.
Because of the human-Time Lord meta crisis, she became part Time Lord and because Donna is a human having The Doctor's mind was too much for her, it was killing her, so he had to wipe her mind otherwise she would burn up.
The Doctor has had many companions throughout the series, including Rose Tyler, Martha Jones, Donna Noble, Amy Pond, Clara Oswald, and many more. Each companion has their own unique relationship and dynamic with the Doctor as they travel through time and space.
Her name is Donna Noble
Donna Noble.
Its Catherine Tate
Extremely doubtful, her story along with the rest of the tenth Doctor's companions were all wrapped up in the End of Time part 2, she is now happily married and very rich, it would also be hard to bring her back as she can never remember the Doctor.
Wilfred "Wilf" Mott.
She first meets him in the 2006 Christmas special The Runaway Bride.
Donna's grandfather's name is Wilfred Mott. He is an amateur astronomer. As far as we know he is retired and he lives with his daughter.
A wedding dress.
His name is Wilfred Mott.
It's unlikley.
Catherine Tate as Donna Noble
SPOILER (but it's in reruns): The Daleks have trapped the 27 worlds and lay siege to Earth. But Donna manages to regenerate a second Doctor within the Tardis and this Doctor destroys the Daleks. Rose and the second Doctor are left in the alternate timeline for Earth, and Donna's memories of her travels with the Doctor are erased to save her life.