Adelae often dies back after flowering. Just continue with the basic care you are giving the plant. Repotting is a good idea, there is always a chance the substrate has been contaminated with mineral salts, esp. if distilled or rain water aren't being used. The plant should regrow offsets from the roots. Mine has pretty much died back after flowering all spring: the process exhausts the plant, but already new offsets are appearing, so it will only be a matter of time. I have found the plants like cool conditions for me, so the cool nights are actually a plus. I never expose my plants to sunlight, but a friend in Brazil grows his in full sun in their hot, hot summer. The plants grown in this way are smaller, darker and hardier. The plant responds to many different conditions. It really hates drying out, even briefly, so keep it very wet. Humidity seems a secondary issue to this: I have plants under 50% humidity that are doing just fine. I think the most critical factors for this species are wet conditions, not too hot, and not too bright all at once. Good luck.