I thought crime fiction couldn't get much better than Purgatory Chasm by Steve Ulfelder. Steve proves me wrong with his follow up The Whole Lie.
Ex-con Conway Sax is still the Barnburners' (sort of like the AA) special problem solver. Savannah Kane used to be a Barnburner and Conway's lover. She returns into his life after seven years. She has some problems involving blackmail and a Massachusetts politician.
When he gets involved his wife isn't too happy about it. Soon people start dying and more and more lies turn up.
Sax sacrifices his relationship and risks his life to make good on the promises he made in the past and tries to fulfill the duties he feels he is honor bound to fulfill.