For myself, were I to reach a state of mind where suicide was an acceptable option, my choice of movies (if I were to go the route of seeking solace in movies) would be about "taking the edge off". It would be about minimizing the depression or despair that would accompany the consideration of suicide. Hence the resort to inspiration or escape. This helped me to thin out the choice of films quite considerably.
The first of the films on the list that fit either one or some percentage of both of the aforementioned categories was "The Shawshank Redemption". As a matter of note, I would place this film in the category of inspirational (specifically with respect to the aforementioned state of mind). The setting of this film is something that I would consider a bit "dark". Its "darkness", however, wouldn't be about any level of evil, but about the despair present in the circumstances of the main character. This would probably be why I might be attracted to this kind of movie in that state of mind.
Based on a short story by Stephen King, "The Shawshank Redemption", directed by Frank Darabont, starring Tim Robbins, Morgan Freeman, Bob Gunton, William Sadler, Clancy Brown, Gil Bellows, Mark Rolston, and James Whitmore, tells of a young banking executive who is wrongfully convicted of the murder of his wife and her lover. During his time in prison, he is victimized by a prison gang on a regular basis until his friendship with an entrepreneurial inmate provides an opportunity to reap unexpected benefits from his knowledge and experience as a finance executive. After enduring 19 years of prison life, usable evidence of his innocence in the form of a cellmate-to-cellmate confession from the true killer of his wife and her lover comes to his attention. But his hopes are dashed by the warden who is exploiting his financial experience for his own gain. After being cruelly punished for his protests, he decides enough is enough.
I can't tell you much more about this movie without telling you the entire film. Being the well told story that it is, it is easy to get caught up. One of the things that stood out to me was the portrayal of the despair that is a part of long term incarceration. In the course of the story, one of the characters, after serving 50 years, is released on parole. Having been incarcerated as a relatively young man, he is released as a senior citizen. Surprisingly enough, he has no wish to be released. He has become what the main character's friend describes as "institutionalized". Prison life has become the whole of his existence. Life outside of prison fills him with fear. Unable to adapt, he is overwhelmed by futureshock. When the main character's friend is released after 40 years, he experiences the same fear and loneliness. That is, until he remembers the favor the main character asked him. "The Shawshank Redemption" is a story with stories in it, all of them good, and all of them connected in one way or another.