Same problem here. I'm beginning to discover something that MIGHT help... but that might just work for me (or for ENFPs in general). No idea. Here's what sometimes helps:
Lots of times the cause is simply stress, or depression, or feeling too frustrated and not at all appreciated by anyone. Once I got picked on by someone with borderline personality disorder, and that was bad too. If my situation improves, then my Ne gets stronger as well.
Doing creative stuff. Doodling. Arranging my CDs according to their moods. Drawing. Freewriting. If I feel I've got enough time to do it and that I'm not under any pressure to produce something worthwhile, then usually it helps me strengthen my Ne, for some odd reason. (I don't think creativity = Ne, but in my own case there's some correlation.)
Being nerdy. For myself that means spending time reading and learning stuff about poetry, writing, Victorian Literature, typologies, and philosophy.
Writing, thinking or talking about theoretical, "philosophical" stuff.
And paradoxically doing something that requires lots functions OTHER THAN Ne. Doing small-talk about trifles, or learning technical stuff. It's like my intuition gets no outlet and becomes stronger and stronger because it isn't used.
Disclaimer: Might or might not help. Might or might not have sth. to do with
Hope some of it helps. Life without
sucks.