I understand what seems to be a [possibly] joyful combination of nostalgic remembrances, and prideful relief, that you have achieved what many of us, wish for! Not only do you understand the extent of your ‘duty of service’, by launching much needed human beings into a world that desperately needs their sort, and genre, as you no doubt can describe, but also, you apparently took great care, and delight, in having an enriched life, thus far, given such a wonderful ability, and such great endeavors. You also seem to have major elements, that will continue to prove successful, beyond and on to the next life chapters, that await, and no doubt, your preparation of your children, now adults, will help you constitute amazing, and exciting adventures, and overcome challenges that will also be deployed in your life span.
This is what I can see from your description of the nostalgic note, and the empty nest sort of grief, and loss, that you may be undergoing, presently. This provisional sense of loss, and possibly with more acute symptoms grief, in some cases, is usually associated with the new demands that a change in status, or self-defined roles, may bring, once the possibly more than two decades-long change in filial-parental relationship changes, because those children, can now benefit from all that you have done, to help them ‘take off’, with effective means, and valuable resources for repeated soft landings, and more than multiple take-offs. Your role as a parent, and mother, as a leader, and caretaker of your clan, will now change, as will be your decades-long routine, and accommodations, and as members of the socializing Human species, any significant change in our social role, takes time, and effort to digest, and finally acclimate.
This is your period of transition, Phoebe. You will be in a position now, to not only experience the emptiness of the nest, but also the fullness of all spaces, and the fuller meaning of all things outside the nest. You can also determine with greater autonomy, what new course of flight you may wish to take, and expand, and the itinerary is fully self-guided, and without restraints, as experienced before, because you are independent of the bonds, and obligations that also kept you close to home, with a great deal dependent on you, and the effort of others helping you, as the most significant resource to so many ‘mouths to feed’, and minds to nurture, and those bodies, and those characters to keep safe, and shape. However, it is also noteworthy to understand that the essence of the love, the tenderness of the elasticity of the bonds that you and your husband have developed with your children, will remain intact, and ready to deepen, as they become their own full human beings, and their reflective sense of you, will cast a resplendence worthy of your hard work, ready for all to see. According to Erickson, and other similar writers dedicated to documenting our developmental stages, as adults, with growing maturity, this resplendence, is part of what may become an integral aspect of your legacy, in what then constitutes Generativity, or a source of deepest pleasure, and achievement, because you are passing on the torch, for many generations to come, and that will survive your individual effort. In an anthropological sense this is what we all seek, to live beyond the limits of our lives, and to extend beyond our years, that which we spent so much effort cultivating, and making just right, with such great devotion, and even blood, sweat, tears, and when luckiest: Joy, and reciprocal Gratitude.
Of course, it is also during these transitional stages in our lives, when all that was lacking before, and all that may have been symptomatic of greater distress, and possible maladjustments, will result in greater degrees of suffering, and perhaps even the emergence of what could be break-ups, disillusionment, and ruptures of cascading dimensions. If this is the case, then of course, diagnostically, we could trace the pathological development to pre-exist, independently of the nest, or the fullness of the nest, or the emptying of the nest. Hence, the here-and-now could present a fine opportunity to deal with those issues, should they be of significant enough dimensions to have you seek treatment.
I hope this is helpful, and if you wish to explore these possibilities further, I can offer you that, as well.
Please take good care, and be well!