More a 4.5
This book gave me all the feels. Holy crap.

Extension:
I love this book, but I wish some things were more explained. I hope that will be more explained in the other books. From what I understand it's a bit like the Anna and the French Kiss series but then in space.

Lilac in the beginning is a bit annoying BUT she does have a really nice development and I love good character development.

I was expecting Titanic in space and that is it, for the first few chapters. It's more a surviving story.