At the end of the movie 'Blue Valentine', as 'Dean' walked away from the home and sending their daughter back to 'Cindy' mean that they separate (divorce or something)?
Or does it mean anything else as you think?
Since it's my all time favorite movie, I've done a lot of research on this one. As per your question, movie ends when Dean walks away crying from Cindy and Frankie. And the ending of the movie is left to viewers opinion. It's an open end.
In the end, Cindy cursed Dean that she wants a fucking divorce and Dean tries to convince her and tells her that he doesn't want Frankie to grow up in a broken home and Cindy tells that she needs space but she doesn't persists that she wants a divorce.
So, based on the scene I mentioned, as an optimist, I thought Cindy and Dean would get back together.
Now, I'll tell you why Derek Cianfrance (director of this movie) wanted to make Blue Valentine and what he has in his mind. In an interview, Derek was asked whether his parents were divorced and he answered:
By the above answer, it is obvious that he wanted to make a movie about the problems in marriages and how it ends with a divorce.
In IMDb trivia, it mentioned;
In another source here states that;
And Derek Cianfrance said;
In the question, you asked, "does it mean anything else as you think?" and despite all the speculations above, I think, Dean and Cindy will get back together.