Sounds flippant, but you aren't losing money until you sell your shares. Even mutual funds are down 25%. You don't even have to wait till the end of the year to take a loss. Sell now and buy the shares back next month.
To be somewhat sympathetic, the biggest loss here is the missed opportunity elsewhere in the market, like shorting everything else or buying at the bottom.
But you will be happy to know your elected officials are still getting their inflation proof raises and full retirement.