Posting this here because I would love to get the perspective of fellow women without children, although I suppose the question is broader. Sorry for the long post but I hope the context is helpful.
Although it has been a few years since the pandemic restrictions ended, I have been struggling to make new friends by doing the usually suggested things (book clubs, university activities, etc; I do not drink or enjoy clubbing, etc). I have always been an only child, do not want a romantic/sexual partner, but crave genuine close friendships -- people I can open up to about my life and feelings, and who truly value spending time with me in the way I value their company. I have been an expat in the US with my parents since childhood, and am currently finishing a PhD at a US university in a city in a different part of the country to where I grew up. I am in contact with a couple of childhood school friends, and sometimes meet up with them when we happen to be back in our hometown for the holidays. But I cannot just pop over to their houses for a cuppa or attend a concert with them anytime during the year, as they live in different parts of the US.
I made some lovely friends at university (bachelors and masters); we did a lot of things together and were very close, but we all moved away to pursue different careers or doctorates at different places. I tried contacting many of them but either was ghosted or got very lackadaisical replies. It seemed like they had moved on with their new lives, partners, etc. and were simply not interested in maintaining our friendship. I enjoy the company of my fellow PhD students now, but again the same thing is happening where we are finishing one by one and going off to different cities and losing contact. Many of my classmates are getting married and having children, and they just don't need/want platonic friends like me in the way I need/want them. I haven't made friends outside the university, as I don't have time for volunteering activities, etc. at the weekends thanks to the level of hands-on involvement in my thesis research.
Anyway, once I finish my degree, I will probably move to a different city in the US, or maybe even back to the UK if the NHS looks like it will get better and general quality of life improves under Labour. (I lived in the UK as a child only so moving back would effectively mean starting a new solo life there, as my parents are well-settled in the US.) Even if I stay in the same city as my uni in the US, most of my current PhD friends will have moved (and I'm not especially close to them like I was to my undergraduate friends anyway). Sometimes I feel very despondent at my lack of genuine close friendships, especially seeing others get married or have strong support networks in the form of siblings and their families. I feel like this cycle of making friends locally, then losing them again when moving to a new city, is going to keep repeating. People always suggest meetup groups, local communities, etc. as a source of new friends, but given my own experience with a few university student groups and book clubs, I didn't make any lasting friendships there. I'm certainly not an introvert or antisocial person, and I'm liked by the friends / classmates / coworkers I have at any given time (they enjoy talking to me and working with me but it never really turns into a really deep personal friendship). I am usually the one who initiates any social outing, but I'm afraid our interests don't overlap closely so the enthusiasm is often one-sided. I am so much more invested in spending time with them and maintaining our friendship than they are, as they already have activities planned out with their partner/children all the time. I also realise that some people probably think I'm boring since I don't drink or enjoy nightlife like the young crowd (I prefer visiting museums/gardens, discussing books/films, etc.)
So, if you are in a similar place in life as me (late 20s/early 30s, single and no family nearby, not deeply "settled" in one city and likely to move for work or education, have a demanding full-time career/degree), how do you handle making new friends that become long-lasting close connections? When all your friends / colleagues are married / have children and are just too busy to invest time in building a closer friendship with you, where do you go to find those friends -- those friends who will truly care for you, who will always be there to lend a helping hand or listening ear, who will travel a long distance to visit you even if you move away from each other?