I know for a fact that I have forgotten LD's. More than once I have scribbled notes in the middle of the night and then in the morning have only the vaugest recall.

The dreams that I remember best are the ones that helped me resolve an issue or a grand adventure. Right now, I am having a lot of trouble with recall due to stress. Stress can cause bunches of problems IRL as well as in dreams. Perhaps learning some meditation techniques would help you. I recommend www.meditationcenter.com as a starting place.