I loved the book, way better than What the Librarian Did IMO.
First of all, I love the friends-to-lovers theme, and this book delivered. Jocelyn & Dan are good friends and make a great couple. 
The book had some funny moments, especially in the beginning. Dan's idea of bullying Jocelyn into marrying him (in a good way, mind you) by planing the wedding is unique, and probably something that wouldn't goo so good in RL, but here it works like a charm. I loved Jocelyn's reaction when she realised it wasn't a big joke. :)
Of course, not everything is so light-hearted. Dan is suffering from PTSD, Jocelyn was seriously ill, her Grandma has dementia, suffice to say that they haven't had it easy. 
Only one thing bothered me a bit, not enough to deduct stars, but still. Jocelyn's 
PLAN. I won't go into detail, but you really have to be imaginative to come up with something like that. 
I loved Ross, and I'm looking forward to reading his book  Stand-in Wife.