Two Doors Away by Elle Spellman
Since moving to a new city, once-adventurous Steph is doing her best to prove to her friends and family back home that her life is as fulfilling and envy-inducing as ever. The truth? She is broke and has found that making new friends isn't as easy as she expected.
Eric has lost his way in life since his breakup with perfect Clarissa. Now that all his friends are buying homes, getting married and starting families, Eric is still living in a house share, feeling left behind.
Eric and Steph are lonely. They're strangers, but with one connection - they live on the same street, on either side of number 26. Neither Eric nor Steph have met their neighbour at number 26, but both used to take comfort in hearing their neighbour playing piano at the same time every night - it made them feel less alone.
Now the music has stopped and number 26 lies silent. Brought together by their mutual concern, Eric and Steph begin to grow closer and it looks like they might discover that the solution to their problems has been just two doors away the whole time.