@Bellbird Those days aren't gone except in the case of estrangement between family members. Once our kids are grown and gone, they have their own lives, friends, jobs, homes, partners, children, and as parents we need to accept that. After all, we had our "turn" at leaving the nest.
The days that are "gone" are the days when most of us lived in small towns, often being born/living in the same place all our lives. Families lived closer then; nowadays it's not unusual for families to live in suburbs of the same big city but still many miles away from one another. For instance, my son lives a 60-mile round trip from me and now with the cost of gas, a once-a-month visit is what he can manage.
Now it's up to us to adjust to our different circumstances. Our kids are raised, some of us are widowed, some retired, some financially secure and some not so financially secure, but we need to make the changes necessary to keep living fulfilling lives. Church? Friends? Part-time jobs? Travel? Volunteering? Taking a class in something we've always wanted to learn? Or maybe even pursuing a degree (or another degree). Whatever it takes to continue to be aware, awake, with it, and not turn into bored old folks. Bored people (no matter their ages) are boring people.
And BTW, in most places, once you've turned 65 and are a resident of your state, college tuition is free. Still have to pay for books but many fees no longer apply to older students, not to mention that student ID issued to students garners a whole lot of discounts!