Supergirl has at least nine “boy friends” that she has “split with”. Based on her expression, not amicably this time (at least). At least one of them wears an ascot.

As they are described as “Supergirl’s jilted boy friends,” it would seem that the boy friends have “suffered [her] ending a romantic relationship with [them] suddenly and unkindly”.

Supergirl cray-cray. QED