Hard to know what to say really. Sort of feels wrong to say I enjoyed it ( a bit like 13 reasons why - you feel compelled to keep listening even when its heart breaking). It's short - only 4hr on audio - but I think the brevity of it is fitting. The sad isn't dragged out any longer than it needs to be, and I think there is only so long that the author would have been able to hold up the lack of plot with nothing else at her disposal other than replaying touching memories vs even more touching visits from loved ones. In a short book it works fine, but it might have got a bit stale if it had gone any longer. Likewise, I love the ending - both it's question mark of what is to come (2nd book aside, I really liked the end) and where in the timeline it occurred. The characterizations are excellent - particularly the teenage romance that isn't a inst-love straight to HEA, but 2 people negotiating their differences and their insecurities, and having rocky patches amidst the good stuff. 
 The audio version is spectacular - little snippets of cello music from time to time and the narrator did an excellent job of portraying the many emotions that Mia goes through (a times I wondered if she was actually crying). A sad, heartfelt read that will linger with me for some time to come.