Ethereum won't reach $5000 - 10000$ in 2018. I can see it reach probably $1k but Ethereum's base points stand within $720-$920.
Ethereum can reach 5k dollars by the end of this year if bitcoin will tough high targets. We all know that ethereum depends on bitcoin for making progress and the future of BTC is a bright one. Crypto experts are of the opinion that it will touch 35k to 40k dollars before 2019 and I fully agree to their statement. When this will happen, ETH will also be somewhere near 5k to 8k dollars.
But I am not seeing big fans for ethererum how many people are heartfully ready to hold bitcoins for years. When the community is not supporting with long term holding, no coin may have a sustaining price levels. Even if it will be touching some unimaginable price levels, it may get a heavy dump following that.