If Clara looks around her workplace and friends she notices a surplus of single women in her age range. This of course puts her at a disadvantage: if she has to compete with women for fewer available men, she will have to trade below par, or in plain terms, lower her expectations below what she could get in a more gender balanced environment.
Our modern world still conforms to an archaic double standard when it comes to the assumptions surrounding a woman who's single. When a high-value man is single he's viewed as "playing the field" or hasn't met the "right woman." When a high-value woman is single it's assumed to mean that men don't want her (for good reason.)