Crypto is in BEAR market and there is no doubt about it. Bitcoin and Ether will continue to downtrend until they find their floor which seems to be between around $3k - $1k and $300 - $100(as per the technical indicators) respectively.
This downtrend is a healthy continuation of a growing market. The market has to grow in cycles where bad speculators and those people who are in just for profit will fade out, and the blockchain and the decentralization technologists/believers will continue to focus in building the technology.
Just to let you know that this is not the first time BITCOIN has crashed, it has crashed several times 2013(83%), 2015(87%), 2017(59%), 2018(don't know yet). Also, most of the alt coins and ICO's are down 90-95% from their peak which tend to make new investors/traders panic sell their position giving them stress and frustration, which is very understandable. As per to me, DO NOT take loss and sell your position rather hedge your position(meaning, buy more when it's down and average it out). Focus on those ICO's which are significantly down but have a great team and world changing concept that truly needs blockchain technology and also values their community. Bitcoin and Ether will come back with a strong rally and much upgraded tech solving all the current FUD's and problems(scalability, lightning network, China ban, Korea adoption, and much more) it currently has.
Questions and answers:
Will Bitcoin and Ethereum ever go up? - Absolutely yes.
When will it go up? - Nobody knows. It might take months or couple of years until it finds it bottom and consolidates.
Which coins to buy for the greatest returns? - Study the market and invest on those with strong executable team, great blockchain concept, and is down significantly(90-95%). One that I have found after months long research is RIGHTMESH(RightMesh is the world’s first software-based, ad-hoc mobile mesh networking platform and protocol using blockchain technology and RMESH tokens to power growth).
What if it doesn't go up? - Well, this is emerging market with no regulations and you should only invest the money that you are willing to loose... It's highly risky but also has great returns, far greater than traditional markets like government bonds, stocks, ETF's, options, currency, commodity, options and others.