I think bitcoin could well reach $2,000 - $3,000 if this $6,000 support get's broken. If you would sell now chances are high you could buy back and thus double your btc holding.
This is not financial advice, just a thought.
And this is not a good year for crypto I believe. Late 2019 we'll see some action.
I think for the current price, it's already late to sell. I suggest to hold and be patient to wait for the bounce back and if you want to cut your losses then buy more coins while it's at lower price. Never sell at this stage if you want not to loss much money.