Despite some of the reviews here that characterize TLG as trite and dated, I only thought this film was a directorial surprise, way ahead of its time for 1949.
First you start with a flashback by Preston's character that isn't quite a flashback, because we are more interested in who this man is and what the circumstances of his plight are, than the past per se. Virtually all Hollywood flashbacks seem to involve some grand police confession or some need to explain the confessor (such as "D.O.A.")but the flashback here seems to add to the convolutedness of the characters, and the surrealism of the situation. Does Preston really understand his wife? If so when? The flashback reminds us that there is more to explain than the "what",but also the "why" which neither Preston nor the audience yet understand (gambling is a disease, but the matter of guilt and personal responsibility for misdeeds remain open).
More convolutedness in the photography. Carefully cropped chest-up body shots, with swirling camera movements amid authentic but claustrophobic interiors. Remember, only Max Ophuls was supposed to have done this sort of thing at the time! I remember "Leaving Las Vegas" attempted the same themes in slightly different ways (misery and anomie in a spectacular setting) but that was a miserable film.
Finally you have a not so sweet resolution to depict insanity, but in a much subtler way than "The Snake Pit" and other entries in the growing body of 'social consciousness' films. Stanwyck was a tough-soft actress, and the scenes where she rolls before a throng a gamblers rarely came tougher in her films. A work to just watch.