Budget on the Back End
You've cut corners and saved for the last couple decades. You've been good about not touching your nest egg. You diversified your portfolio well and weathered some economic downturns. Now that you've reached the end of your work life, you've got a substantial treasure chest that's all yours. Don't blow it.
Create a budget you can stick to just before you retire. After years of creating new budgets as your net worth grew more and more positive, you should be a pro at making budgets by now. This is not to say that you have to look forward to living frugally for the rest of your life, just wisely. What is it you've always envisioned yourself doing when you retire? If it's travel, then create a travel category as a monthly expense in your retirement budget. If it's spending time with your family, then create a "spoil the grandkids" category.
You can still live your retirement years the way you like; sticking to a budget will help keep you from outliving your nest egg.