As for your debt, I would suggest that you pay off the $10,000 @ 10% first.
Then pay off the $21,000 @ 3.99%.
This will leave you with $49,000.

I would look at your mortgage to see how much of it you’re deducting on your taxes. It might not pay for you to pay off your mortgage because you might be getting a great deduction from it. Also, if the mortgage was just in your husband’s name, you might want to talk to your estate attorney to see what options you might have about paying it off/canceling it. Remember, if you pay off your mortgage you lose that deduction after the year your mortgage is paid off.

I would then suggest that you contact your student lender and inquire about canceling your student loan based on economic hardship. If you’re recently became widowed, have kids to raise and are struggling month-to-month, you would probably qualify. You’ll have to fill out forms and show your income. But it could save you $10,000. And right now, every dollar counts. Remember, the insurance payout that you got does not count as your income.

I would then really think about what you want to do with the remaining $49,000.
You don’t want to gamble with this. You can use it to build your next egg. But in a volatile market like this, your best bet might be to play it very safe and invest some of it in tax-free treasury bills/bonds until the market really starts to rebound and moves upwards for at least 6 months.

I would not invest any of your money in regular stocks/mutual funds or ETFs right now for 2 reasons.

1. You want to hold on to that $49,000 because it could be the last big pay out that you ever have. And you want be very careful with it because you want it to provide you with security for a very long time.

2. The market is too volatile right now. If you invest $10,000 and it goes down to $8,000 (a loss of 20%. $2,000 is 20% of $10,000), your $8,000 investment now needs to rise 25% to regain the $2,000 that it just lost to get back to even (25% of $8,000 = $2,000). Remember, it always takes more performance for an investment to rise than it does to fall.

You can also open a Roth IRA and deduct your investment from your taxes next year (if you’re not already in a 401k plan or retirement plan.)

Whatever you do, just make sure that you work out the numbers for every scenario before you commit to investing. This way, you’ll know exactly what you’re saving.

Good luck.