1k is very far to 18k. Ethereum will not defeat bitcoin in just one year. Even ethereum is in good vibes still bitcoin is undefeated. Bitcoin will stay at the line of the number one in crypto. Maybe before the end of 2018 it will reach 5k in December 31, 2018.
Of course the price of ethereum is difficult to reach $18k in this year but it can reach $5k even $10k in this year. Although Ethereum which have many advantages about technology than Bitcoin, will soon replace bitcoin to become leader of cryptocurrencies market in the future but it need the time to do this, i think it's need at least 10 years to the price of Ethereum equal the price of bitcoin now.