You don’t have to ignore Ashton, you can be civil – or polite, but distance yourself as a friend. It’s hard to do, especially at your age.
My daughter went through something similar to this, because she didn’t want to hang around a certain group and a few of her friends “migrated” to the other group. My daughter stopped seeking them out, as friends, and went on to hang out with the rest of her friends. A few of the ones that she had stopped talking to, as much, have “rejoined” the group and even apologized for how they were treating the others. She’s cautious, protecting herself from any further issues, but is slowly warming up to them.
Try to talk to her, but distance yourself. I know it’s hard and believe me, we’ve all been there! You may not think we know how you are feeling, but we do.
Good luck!