I think some people always need to have someone special in their in their life and feel emotionally vulnerable without someone, Women in particular, in the past, including our generation, were often brought up to measure their success in life by whether they are married. That deeply inculcated belief, is still there no matter how financially independent and successful their career, so if they find themselves alone they are vulnerable to advances from younger men.
It is not just women, a gay friend of my sister, was left alone when his partner of over 30 years died, within a year he was wooed and won by a much younger male Thai bride, and is slowly and quietly being bled dry by this young man. My sister doubts the marriage will last longer than the money.
Like others I find it difficult to understand, but I wasn't conditioned to measure my success by having a partner and I am a self-contained person who is quite happy in their own cmpany.