Rumour about my boyfriend Watch
Relationships are built on trust. You clearly don't trust your boyfriend enough to listen to his EX (who clearly doesn't want you together) instead of straight out asking him. If he's done nothing wrong to you that's given you any indication why doubt him. Speak to him and not just listen to his ex.
I wouldn't believe anything she has to say. If she's using a fake SC, her intentions could be sinister, as if she has something to hide. Unless she's willing to reveal who she is, you should definitely be cautious
You either don't trust your boyfriend or you are too easily swayed.