Movies such as “It’s a Wonderful Life,” have explored the subject of a life re-examined when contemplating suicide, but Courteney Cox takes a darkly comic approach to that life-or-death question in her feature film directorial debut. The story of a vacant, aimless pet store worker named Ted who decides he is “done” with life, “Just Before I Go” begins with the dejected 40-year-old bobbing underwater while narrating his tale of woe on the soundtrack. The film then travels back in time several weeks to explore just how he got there.