Utsuro no Hako to Zero no Maria 1 by Eiji Mikage
You know what's amazing? It's only been 18 years since the film Groundhog's Day popularized the infinite time-loop story . Less than two decades, but the concept has become a staple of sci-fi television -- it's hard to think of any SF show that hasn't had a Groundhog's Day episode. And yet there are surprisingly few literary takes on the concept, and off the top of my head I'm not aware of any novels that use the concept.
(You! Yes, you. The guy who's about to say, "What about Ken Grimwood's Replay?" Don't. Being able to relive large portions of your life isn't the same as being forced to repeat a short time-span ad nauseum. A single day or a week doesn't allow much variety for your experiences, or time to see any effect from your actions.)
Utsuro no Hako to Zero no Maria (0's Maria and the Box of Oblivion) is the first lengthy prose work I've encountered that tackles this idea. And whereas most TV series that use the concept follow Groundhog's Day approach and treat it as comedy, Eiji Mikage chooses instead to focus on the horror of the situation . It helps that the characters are all high school students, which greatly limits their freedom of movement. Just imagine being trapped not just in trigonometry forever, but having it be the same lesson. A show like Stargate can have Jack and Teal'c go through hundreds of repetitions and come out unfazed, but Mikage knows that anyone in this situation would be going crazy after the first thousand cycles.
Most Groundhog's Day stories go in one of two directions -- either everyone is ignorant of the looping at first, but then gradually begin to experience deja vu; or the protagonist is aware of it from the get-go and has to reconvince those around him in each iteration. However Mikage takes the story in a direction I've never seen before (though the "Endless Eight" story in Haruhi Suzumiya did something sorta similar): Kazuki Hoshino, the main POV character in this book, is actually one of the poor dumb bastards who doesn't know what's going on, and he's constantly perplexed by Maria, the only person aware of the loops (other than the person causing them).
But some of Kazuki's actions make Maria suspicious that he's the one causing the loop, which draws her attention across multiple repetitions. After a while, her constant attention starts to break down the barriers to his memories and he's able to retain some information across resets.
The book is really well structured. Because Kazuki's memories are imperfect -- even once he gains the ability to remember past iterations, the power is inconsistent -- Mikage can use anachronic order to withhold info from the reader without it feeling like a cheat. Every time the story starts to get comfortable, he slips in a revelation that changes everything. The first of these came as quite a shock as it seemed to give too much away -- only 20% into the book and he's already revealed who's responsible for the loops. But then the next revelation would come along and call into question what had gone before.
This pervasive uncertainty, combined with paranoia about who is causing the loop, gives the story a very creepy Phillip K. Dick feeling that suits the plot much better than Jack and Teal'c shooting golf balls through the Stargate.
 The concept itself dates at least to the 1973 short story 12:01 P.M. which was actually turned into a telefilm the same year as Groundhog's Day, however only anal-retentive geeks like me know of 12:01 P.M. while everyone's familiar with the Bill Murray movie.
 I understand that early drafts of Groundhog's Day actually did treat the subject seriously, even suggesting that Phil spent thousands, if not millions of years repeating that day.