First, as a frequent reader of yours, it is no surprise that this post garnered 273 response. Let me apologize for not seeing this post sooner.
Your post reminds me (as a soon-to-be 70 year old white male) that age in general robs all of us of our social visibility. I suspect that it hits women earlier than men but, eventually, it becomes true for men as well.
And truth be told, most women have superior social networks compared to men. As a broad generalization (with the limitations inherent in such statements), men of my generation and older tend to be socially dysfunctional -- at least compared to women of the same demographic.
Perhaps, we would all be better off if, as we age, we redouble our efforts to make enduring social connections independent of monogamous or even polyamorous relationships.
Last point: Please keep writing.