The expectations were quite high for this movie since the writers, directors and cast are all well-known names with a good reputation in the Turkish movie industry. However, the expectations weren't met and this affected the experience badly beyond the actual quality of the movie.
In fact, this movie is a nice drama. And if it were a pure drama instead of trying to be an (absurd) comedy at the same time, I think it would be a great movie. Even though making a good drama movie should be harder than making a comedy movie; failing in comedy is also easier and as simple as failing to make people laugh. Unfortunately, Azizler(Turkish) or Stuck Apart failed on that for the most part. Besides, absurdity in this movie felt over the top and unnecessary. One might say that this over the top absurdity harmed the comedy further or even the succeeded drama. All in all, these factors contributed to the fact that absurd comedy and drama didn't match well for this one.
Whereas the drama around "loneliness" was pretty solid. We have characters with different types of problems with loneliness and this contrast gives a nice depth to the story. The acting overall was pretty good too, as expected. Engin Gunaydin as the leading role was flawless. Haluk Bilginer was also great as "Erbil". I truly liked Erbil and his character background was beautiful.
In conclusion, if you remove or ignore the discordant absurd comedy parts, you will have a well-done drama. So I think this movie still worth a watch. But as a drama rather than a comedy.