Anyway, your first line is just sad. Yeah, they are having sex with other men, but is your ego so fragile that the idea of a woman having one or more comparison points scares you?
A lot of my best friends are women. Recently I went through a major accomplishment. I had five women friends text me to congratulate me.
I feel that I dress well, and I am a physically fit marathon-running, motorcycle-riding, outdoorsman. Social awkwardness yes but I think it comes across as being sincere.
This is my unhealthy mindset talking (perhaps) but it isn't necessarily low ego, it's just life, pop culture, etc does not align with the values I was taught as a child, growing up in a conservative religious home.
I know several people who stayed single late in their lives, and they are happy and have many friends. I know some others who married late in life, and they are also happy.
Anyway, I am sorry to hear about your struggle, and is something I am having troubles relating to since I grew up in a colture/family that is very open about sex.