Didn't see a thread on this one so here's my take... This one seems to have gotten not much love out there for some reason. But, hey, it's well proven that bad taste is not adversely affected by global economic conditions. I thought it was quite enjoyable. It's a Romantic Dramedy more or less, and doesn't follow any of the usual clean story arcs, so some people may not get it. But I think it worked quite nicely and had plenty of funny moments and a good mix of dramatic elements.
The main character is played by Greta Gerwig, who I first saw in my previously reviewd "Damsel's in Distress". I enjoyed here in that and in this. I think she's very beautiful in a non-in your face way, and very likeable. She's turning 30 and in her apparently dream relationship, when it all starts to go south. She's never really been out there in the game, and has to jump back in and isn't in good form, so she makes quite a mess of things ultimately. She doesn't end up driving off into the sunset with her dream guy in the end, she just has come to some sort of clarity really.
Her best friend is sort of the standard 'cynical one liner' friend that often shows up in movies, but she has some good cynical one liners. "Find your spirit animal, and ride it till its d$$k falls off", and that sort of thing. She provides some of the best laughs in the movie. Some of it is obviously generation specific, like the obsession with phones and texting and such, but most folks here probably will more than get that humor I imagine.
Anyway, I think the low rating is undeserved, and it's a quite enjoyable flick if you like those sorts of movies. So give it a shot.