I read this for free through First Reads.
The book started out with a bang - a very good start, but seemed to slowly lose focus. I liked how the book switched from past to present, but sometimes it was difficult to differentiate where I was (now? then?). I liked the contrast between the character's then and now, but there seemed to be little real change (in attitude - pessimism vs. optimism) until the last few pages.
Kudos to the author for - I believe - not being a native English speaker, but the phrasing was sometimes awkward and hard to overlook. For example, I'm really picky and get annoyed when someone writes "cause" instead of "because". The dialogue was a little awkward because to me, it seemed like a lot of overshare; it's hard for me to imagine someone talking that openly. Sometimes the Polish was too strong - a literal translation - and too awkward for the English. I also thought it was a little strange that some names were changed to English equivalents (Kate, Erica) whereas some stayed in the Polish (Stanisław, Janek). there were many instances of really beautiful, descriptive writing.
Overall, I think the character was very dramatic, but I did enjoy the read. I found it a little difficult to relate to the main character because I have always tried living with the motto "it could always be worse". I was, in a sense, proud of the main character for finally going that direction as well.
And, of course, it was nice reading a book set in my favorite Polish city, Gdańsk.