Solo her

After a quick look at her stats, she hasn't leveled up at all yet. Using soul crush would be pointless since she still has 1 Mdf. You'd rather save it for another illusion spell. If you need it, it should last 19 seconds, more than twice as long as last time.

You cast your first illusion spell, running towards her firing off your attacks. You're almost surprised at the increased damage from your level. It's still not much, but the fight will go faster now. As she nears the red zone of her health, she pulls a red vial out of her bag and drinks it restoring her HP.

"Glad I bought that health potion. Definitely worth the rest of my gold."

Well, now you know she doesn't have another. Your spell of illusion fades and you recast it before she can get a hit on you.

It feels like forever until you finally knock her health back down to red again. She turns to run and you trip her, stopping her from running and knocking out most of the rest of her health. Unfortunately, since she hasn't leveled up yet, she didn't give you enough experience to level up again. Maybe you should have let her take out a few ghosts first to level her up.