Lee McAvoy
From Tardis Wiki, the free Doctor Who reference
Lee McAvey was at the Library during the attack of the Vashta Nerada in the 50th century. He was saved, like all the others, by being uploaded to the hard drive of the computer.
At some point he was introduced to the newly downloaded Donna Noble, by Doctor Moon. They fell in love and got married.
While getting rescued from the computer, Lee and Donna lost each other, leading Donna to believe Lee wasn't a real human. It turned out that he was a human after all, but since he stammered he coulnd't call out to her when she left with the Doctor. (DW: Forest of the Dead)