SOLVED. PI is hired to look for a missing wife. Discovers that the wife is his neighbour. [s]

[Jo-Lee]

Neighbour is impersonating her twin sister to help her hide from an abusive husband. Takes up running which she hates to get a similar look to her sister.

[Rc]

Broken by Shiloh Walker?

[Jo-Lee]

i think thats it thanks!

[Rc]

You're welcome! I was surprised when I came across that one because the details you gave suddenly seemed so familiar...I had no idea I'd read the book you were looking for! :)