I'll proffer you an option.
1) Trade options. If you have the means to self-direct your retirement accounts and you can upgrade your accounts to be able to trade options, then you can buy what are called "leaps". So you buy a call option whose contract expiration is 1-2 years out. You buy it a little bit out of the money (so above the current price) and then when that stock or ETF rebounds you can trade the contract away and make almost as much as if you had held the shares in the first place. If that stock or ETF doesn't rebound, then you are just out the slight amount of money you paid for the contract.
It's about creating synthetic trading leverage without having to put all your cash at risk. Yes it sounds incredibly risky, and it can be, but if you learn how it works, DO NOT use margin to over-leverage, and you have some diversification to your strategy, you will be successful in the long run. You MAY not necessarily get the full return of the market at large in the "best years", but you will have capped downside risk for times like this. So in the long run you are doing better. I wish I had learned about options trading sooner, or rather, had the patience to learn it sooner.
The part I like most about options is that when I have confidently placed a trade, especially a leap (in excess of 1 year before expiration) I don't have to worry or watch it closely. I can check back in a few months later, maybe the dynamics have changed and it's worth holding the option a little longer or trading it for profit... Trading actual shares is scary and I did that for the last 4 years... It hasn't been pretty for me on my current holdings this past month, but I've freed up a little cash to buy options representing the actual shares I would've bought otherwise and I didn't have to put all my money on the table to partake in the action of the stock. When there is a rebound I'm now positioned to get the gains as if I had purchased those additional shares, but if for some reason it doesn't? Well then only half my account (the shares I still have for collecting the dividends) will stay depressed, the rest will be in cash still.
2) Learn transferable digital skills. The economy is changing and you might have to make a change.
3) The time to develop "delayed gratification" or adjusting your living standards is NOW not later. Maybe watching sports 5-6 days/week is no longer your thing because cable/streaming costs too much. Being able to learn to let go of the things that will change and may never come back is now. That will make you emotionally resilient and ready to respond to opportunities that come your way. Wallowing makes people miss out because they are too wrapped up emotionally to see the potential benefits of something new in front of them.