Examples of using "неделями" in a sentence and their english translations:
walking for days, weeks
That stubborn pattern persisted for weeks
but she had died three weeks earlier.
Hunting won't be this good again for weeks.
We've been eating the same thing for weeks! I'm fed up with it!
By midwinter, it can survive for weeks in this deathlike state.
The fact that you disappear for weeks with no apparent reason bothers me.