I only read the first 2 pages of this thread because I couldn't handle the enormous amount of bad advice you are getting. Hopefully somebody told you what I am about to tell you in the remaining 2 pages I didn't read.
But in case nobody did ...
You now have $58,000. The $7,000 loss is irrelevant because you can't change the fact that it is gone (it's a sunk cost), so quit worrying about it.
Since this money is for buying a house in 2020, sell your index fund tomorrow and put it into an interest bearing account. You can't lose money in an interest bearing account, so you won't be losing sleep at night worrying about losing your house down payment. Keep adding to it like you have been doing and whatever you have in 2020 is what you can use to buy a house.
I don't care what the market does between now and 2020. Absolutely positively DO NOT put this money back into the stock market (or bonds, or gold, etc.). This isn't meant as an insult, but you obviously do not know what you are doing when it comes to investing. Until you do, stop putting your money into any investments except interest bearing such as a money market or a CD.
I saw at least one person tell you to put your money into a bond fund. When interest rates are going up, bonds lose money. Interest rates are going up and will continue to go up. DO NOT BUY BONDS FUNDS NOW!
As far as the money in your retirement accounts are concerned - If you are not interested in learning how to invest intelligently then just buy and hold. Buy an S&P-500 Index fund or ETF and hold it until you plan to retire. This next part is crucial - make sure you reinvest dividends. The majority of your gains over the next 20, 30, 40 years will come from the growth of those reinvested dividends. If you do this one thing then you will outperform 80% of professional money managers in the long run.
A lot of people will tell you to diversify into bonds, gold, oil, real estate, etc. This is stupid. The S&P-500 is already diversified into every aspect of the US economy. If you own an S&P-500 index fund then you are already fully diversified. No amount of bonds, gold, etc. will make you more diversified.
Stay away from gold (unless you really know what you are doing). Long term it is the worst investment out there.
If you do want to educate yourself then google "trend following". It is an investment technique that tells you what direction the market is moving in allowing you to know when to buy and sell. Buy a bunch of books on the subject. Get historic market data from Yahoo Finance and backtest the techniques you learn. The trend following indicators I use started giving sell signals at the beginning of November and the main one I rely on gave a sell signal last Friday. I sold everything Monday morning (except for my Tesla puts which made $2,000 as it crashed).
For what it is worth. I have an MBA in finance, I trade stocks for a living, and I wrote the book Five Ways to Beat the Market (shameless plug). I do know what I'm talking about.
If you made it this far ... Good Luck!