People are almost always coming from their own perspective. As a woman I found that I (mostly) received three sorts of comments. One from those who hadn't found a great love and wanted me to know I should feel lucky that I'd had something nice (like your jealous rival), the I can't imagine comments from those who were also happily married, and after a little time had passed, a bizarre subset of comments from women who felt trapped in their marriages and seemed to envy my freedom from all of that. (Didn't they ever hear of divorce?)
As for your second strange comment maker, I haven't heard anything like that, how awful! My sense is that she was oversharing her if-it-was-me thoughts, and that if she's not mentally ill (big if there), she probably felt really awful about how that sounded afterwards.