Your estate plus social security should provide a very nice quality of life for your heirs. You should not need any insurance. If you are over 50 add up your 401k, outside investments, house or houses, PBGC, social security ect.. Then decide just how rich you want your wife’s next husband to be!
The one thing I would advise spending money on is excellent estate planning. Time after time you will see someone build wealth and pass away. Strangely their now rich spouse meets someone else often younger and remarries. They love and thrust their new partner and have him promise to give most of the estate to your kids who should receive it. In the end your estate goes to the new spouse and passes on to his or her kids. The generational wealth you built for your family is gone!