Since You Checked Out (Paperback) by Tori Gracen (Copy)

For six years, Ellie Santaclaire and Matthias Sager have been everything except what they actually are.

Best friends.  Coworkers.  Each other's emergency contact.  The first person they call with good news and the only person they want when everything falls apart.

Everyone assumes they'll end up together eventually.

But between Ellie's crippling anxiety and Matthias' toxic habits, every time they get close to that inevitable, they can't seem to fully cross the line.