Plant is sick...real sick

My ladies are now 8 weeks into 12/12. One of the plants has been struggling badly. She now appears to be on her death bed. In the beginning I thought it was nutrient lock-out, so I flushed her. Then when things continued to decline, I started feeding her nitrogen/ Cal/mg. She still didn't respond. Now, all of her leaves have turned yellow and died. There is literally no vegetation left on the plant. Her flowers, though premature, remain green. It's strange because her sister, taken from the same mother, planted in the same medium, and administered the same nutrient cycle is doing fine. Any suggestions? (sorry, no pics)

we could all sit here and take queses at it, but till we actually see the problem, we probably wouldn't be offering much real help..

Have you checked the soil ph and been phing your water? It is kind of weird its only one of them, especially if they are clones and they are getting/under identical conditions.

"There is literally no vegetation left on the plant."
Ouch, thats a bummer. sadly the plant is not going to do nowhere near as good(yeild wise) as it would of and their is nothing you can do about it. so i wouldnt stress over it. I'd let the trichs go milky and then chop myself. you can wait for ambers if you want but imo and in my experience its better to just cut your losses and free up the space for more plants.

I apologize for not having a photo for you guys. I'm digitally impaired at the moment.
I know she's too far gone to save her, which is a shame, but that's life. It's just curious that one plant would up and die like that while the others around it would thrive. Not only that, but its decline and ultimate death happened so quickly. From green to gutted in 8 days. It's like the life (chlorophyll) just got sucked right out of her. She had never displayed any yellowing of the leaves prior to last week, but it definitely seems like some kind of nitrogen lock-out. Oh, well. You win some, you lose some.