I think you only need one true friend to be happy. I have a lot of friends with whom I do hobby stuff, a couple of closer friends with whom I talk about personal things more often, and then exactly one single friend I’ve known for like 8 years where we talk every single day and know absolutely everything about each other including our most evil and cancellable thoughts and behaviors.

I would not care that much about losing most of my friends and would be disappointed but not terribly so with losing my closer ones, but if I lost that one friend the quality of my life and mental health would legitimately plummet. I think for most people they use a spouse to fill this role, but both of us can honestly take or leave IRL romance and sex so this works fine for me and is way less stressful. I do sometimes wonder if it would be emotional infidelity to maintain such a friendship if I ever did get into a serious relationship, because I have a hard time imagining that I would trust or care about somebody I dated more than that. I think if it came down to an ultimatum I would drop the romantic partner every time.