Women tend to be especially attuned to mothering. It's built into us physically and hormonally, and it often becomes a huge part of our self-identities. You're experiencing the downside of that wonderful gift. It's often hard to watch our children keep growing and developing, leaving our arms or our days less occupied. And we can become so focused on unfulfilled desires that the family we already have, no matter how wonderful, somehow becomes "not enough."
Sometimes it's possible to come closer to peace and understanding by these means:
1. Initiate a practice of mindful appreciation for what is already available. This takes us out of our past, out of our dreams, and out of an imagined sense of loss which may never become more than a faint sketch in our souls. It puts us squarely into our lives. We usually discover there is so much richness right here that our longings, fears and hopes become far less significant. Happiness and satisfaction increase exponentially. And living in a wished-for future blinds us to how much joy and sheer amazement exist now. Now is the only moment that is real, and too often our thoughts, desires and fears keep us from experiencing it.
2. Turn some of your available love toward other children who desperately need it. Hospital nurseries often need volunteers to snuggle babies born with exceptional medical or family needs. Or make yourself available to other young moms who could use your wisdom, experience, and time so that they can get a desperately-needed break.
3. Make an extensive list of pros and cons. Give it some real time and attention. There are always good reasons to have another child – usually based on feelings, which can fluctuate with health, hormones, age, and the general state of satisfaction with our lives. There are as many good reasons not to have another – usually these arise from practical considerations, including a good, clear-eyed look into your future for the next 18 years or so. Creating another person has enormous consequences, for the parents, siblings, and the world at large. There is no higher-impact choice a family is ever likely to make.
Blessings to you and yours.