Being a parent is hard. You hear that all the time. You hear how it is hard on the parent. How it is takes its toll on their sleep, their creativity, their career. No doubt. Try performing a financial analysis on 3 hours sleep and you'll know this to be true.
But it is also hard on their community, their friends, their lovers, the rest of their family, those who require their love and attention and sensitivity.
I have often maintained that there is no limit to the love you can give and receive and I still believe this to be mostly true. Life has a way of making room for one more when it really matters, and getting and giving love has a way of expanding ones loving capacity. So I don't think it is can be said that being a parent uses up the love one has to give, I think that would be simplistic, and in the end, a bit nihilistic.
I do, however, that one can only do so much active listening without expending significant effort, and being a parent involves a lot of listening. Empathy. Honing your input levels to understand a human being that cannot yet express themselves well, be it through limits in language, or simple immaturity. WHAT do they want? Why do they want it? Should we give it to them? How do we express what we are doing and why we want them to do certain things and why some things are "NO" and others are "YAY"?
And these questions are not terribly dissimilar to the questions one might ask oneself about those they care about if they wish to be a good friend, because part of being a good friend is, in the end, being a good listener...taking things in, analyzing what others are saying and wanting, and finding way to be help, even if helping is just understanding.
But at the end of the day I think many new parents are done with listening. All day they were trying to figure out why their kid suddenly hates blueberries and why that one puppet made them cry and do they really hurt when they say "owie" or are they just exploring a new way to get attention. They are also listening for deeper cues: is their child happy? Well rested? Did they hear the beginnings of a cold or a sad note where they shouldn't have? Is their child listening in kind? It is a crash course on multiple levels of communication and it can be draining.
I think this is why you see those gross article on how to treat a new parent that imply you should expect your new parent friends to be, basically, selfish assholes who have no room for you and your problems. I don't like those articles. They aren't helpful and they aren't fair. They put child rearing outside the normal flow of life and issue directives on how to treat people like they are sick or needy, or children themselves. They grant permission for people to become poor friends, bad neighbors. A friend is a friend, and sometimes friendships are uneven, but there is rarely a situation that should issue a directive that one friend does all the work, especially one so common as parenting.
I think, in the end, it would be more helpful to explore how to handle the saturation that occurs from opening your mind and heart to input all day, and how to harness that so that we can all have families, and still nurture other meaningful relationships.
I also think understanding the source of the exhaustion can be helpful in defining what is truly draining, vs that which might just be challenging, but ultimately rewarding.
That being said, I frequently feel like apologizing these days when I find myself directing inward in the company of adults, when I find myself tuning out, or getting frustrated that an adult is having a hard to efficiently communicating a need. I realize that this is just part of being a human, interacting with other humans, and I do no one a service by refusing to listen. In fact, all I do is make myself work harder in the long run to maintain the love and environment I want.
One of my favorite things about having a child is that it is an ongoing lesson in the many facets of what makes love and life work (or not work). Some of the lessons are easier to understand, and simpler to integrate. Some simply restate an ongoing challenge you have struggled with your whole life.
Either way you grow, if you allow yourself.