Diane Holmes
From Tardis Wiki, the free Doctor Who reference
In 1953 Diane Holmes was a pilot. On December 18th she, John Ellis and Emma-Louise Cowell were on their way to Dublin. But somehow the plane (Sky Gypsy) flew through the Cardiff Rift and ended up in present day Cardiff.
Diane and Owen had a relationship, but she decided to fly away and try to find the Rift again, to get back to 1953. Whether she succeeded, or if she was killed or otherwise lost in the attempt, remains unknown. (TW: Out of Time)
Later, an apparition claiming to be Diane appeared to Owen after he opened the Rift. This was later revealed to have been a vision caused by Bilis Manger. (TW: End of Days)
 
