My daughters are fully-cooked adults and we are not friends. We are very close, but I’m still the mom. I don’t generally give unsolicited advice and almost never made demands, but there are still boundaries that are different than with friends. One of the best things for me about being the mom of adult people is the shared hobbies and preferences that we hold. One of my daughters and her husband have a small book group that I’m included in. Super fun. I think the casual and organic communication that we share is what keeps us closest.
I think that it comes down to the type of person your child is. When our older son visits he will sit with my husband and watch tv and just hang out. Our younger son enjoys watching tv by himself and is a very different person. He’s not the “let’s hang out type” but is still a wonderful son. I would not consider either son a friend but it is enough to know that they enjoy being with us.
As a parent of both a son and a daughter, I don’t think that gender is really a factor. It’s much more about personality and individual interests. And it fluctuates over time. Sometimes I’m more or less involved in the lives of one kid vs the other, depending on what is going on in each of their lives.
I think my own personality and interests are also a factor. I’m not just mom; I am a person that my kids perceive and relate to in a way that is evolving over time, but also rooted in my lifelong habits, interests, talents, communication style, etc. So that’s going to be a different dynamic in each family.
If you get along, if the mutual respect and trust are there, if you do get time together, I don’t understand why it needs to be characterized as “friends.” Nor the implication that, if you aren’t “friends,” there must be something askew.
I care more about the quality of the relationship than the term or label. The main way to get and keep a good relationship is in the communication. Part of that is communicting respect for them, their decisions. When to speak, when to be silent. But also expecting that back from them.
Imo, it’s also fine to admit you want them to come home at least once/year or, if local, come to dinner, run an errand together, go to the movies, or whatever. I’m interesting IRL and they know it. But the starting point of our relationships go so far back that there’s no clean break from Mom to Friend. A huge part of how we get along IS that long history, the shared past.