No it doesn't.
Sexism is prejudice or discrimination based on a person's sex or gender.
prejudice or discrimination based on sex
prejudice, stereotyping, or discrimination, typically against women, on the basis of sex
prejudice or discrimination based on sex or gender, especially against women and girls.
actions based on a belief that particular jobs and activities are suitable only for women and others are suitable only for men
What definition of sexism are you using where discriminating against what sex you want to date isnt sexism?