Right, it reaches all-time-highs around December and didn't stop and we though that its not possible for it to go above $1K but it did as high as $1200 so don't count ethereum yet because its too early to tell.
Right now though, just like bitcoin, it suffered a worst downfall and even go as low as $600. So that's almost a 50% drop already from its previous high.
But I think that its early to say that it can't go back to $1K. Its that the market is so volatile today and every altcoin is tied up to bitcoin. So if bitcoin goes down, it bring most of the top 10 altcoins.
But I'm sure that $1K is still possible or even more at the end of the year.