Book about twins switching places

[Trisia]

I read this book in 2009 and I haven't been able to locate the hard copy of the book that I own. It's about twin sisters one girly and the other into fitness. She worked in a gym I believe.. so girly twin recently got engaged and she was set to met the guy's family but she had plans to meet with some other guy so she asked her sister to take her place. While the other twin went to meet the family she started a relationship with her 'fiancee's brother who is a private investigator and he figured out that she was not who she said she was.. I can remember scenes from the book as if it was yesterday but I just can't remember the name. Any help would be appreciated..

[Kris]

Trisha, what's the tone of this contemporary romance - romantic, funny, angsty, steamy, etc.?

Do the twin sisters get along very well?

What's the location - country, region, big city/small town?

[☯ DαякєηRнαℓ ❛ ᶜʳᵒᵘᶜʰᶤᶰᵍ ʰᵘᵐᵃᶰ ; ʰᶤᵈᵈᵉᶰ ᵗᶤᵗᵃᶰ ❜]

*following

[Trisia]

Its romantic, a bit steamy. The sisters got along well. They weren't extremely close but they got along. I can't remember what the setting was like.

[Trisia]

I believe small town, the family was wealthy and the brother had a separate cottage a stone's throw away from the main house

[Kym]

Stand-In Bride / The Sister Switch by Julie Kistler?

[Lobstergirl, au gratin]

Trisia, are you still looking for this or did you find it?