I don't think she's toxic. She doesn't know anything about what's going on between between Aurora and Asa, so it's not like she wants to thwart their happiness. But I agree that, right now, Asa is being a pushover and even a people-pleaser, trying to make everyone happy when it clearly is impossible...
I mean it's not about her getting between them, but its really not like she's in love or has feelings either, she's just with him cause he was the next person to go to after she broke up with her bf cause of the workshop distance etc, and she doesn't even care that he doesn't like her, so...
Asa is stupid and a pushover and sarah is toxic and selfish periodt .