Don't trust that bitch, if he have a boyfriend why would she get jealous to him getting close to another girl? She's clearly willing to cheat in order for people to like her or love her, she's one of those girls who thinks the world revolves around them.
I find jealousy cute, why? Because that's when you know that she truly loves you and doesn't want you to drift away, it sort of like she don't want you to get tired to her or dumped her.