You could have jumped out before you lose so badly. And right now, you are at over 50% lose. You shouldn't sell because you have been holding all for years with hope, so why not continue holding.
That's why we have to make believe in our instincts and have to follow it when the situation won't get under control. I would do agree with you not to sell the coins at the moment because if you have held it for a very long time then why would you are selling it right now. Perhaps holding would be become a helpful move.