I felt the same way for a long time. I saw people less physically attractive, less intelligent, less nice, less everything in happy relationships. I tried dating, but couldn't find what I wanted. I realized that the issue for me is that I prefer not to be in a romantic relationship. This does not mean I am alone. I have built a community of friends, but romance is just not something I desire. When I tried to meet people on dating apps, they were looking for serious relationships or casual sex (neither of which I wanted). Anyway, not sure what the issue is for you, but that's how it is for me.