While trusting in Delphine may have been in question throughout the series — it has always been revealed that Delphine had good intentions and always had Cosima’s best interest (her health and safety) in mind. Personally, we would have loved a scene where Dr. Cormier explicitly dumps Leekie because they were clearly involved in some weird, intimate capacity — but we’ll head canon it. Once she realized she was in love with Cosima — which Brochu has suggested was ‘automatic’ or immediate, she’s been true to her since. Her methods may have been sketchy but she did her best with proving to be on the clones side and always doing what was right.
At the end of the day, Delphine was true to herself and did what it took to keep Cosima safe. Cosima knew this as proven in the finale during their heartbreaking goodbye scene.
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