It's possible you are noticed less now because the women in your age range just aren't looking to date because they're already in relationships. I'm not sure if partnered women really look at men the same way heterosexual men look at women. I wouldn't let that bother me. When we're young we tend to look more at prospective mates and partners but not so much after the 20s and early 30s, at least in my experience.

I'd work on the self esteem issues. Have you considered therapy?