I don't think that jail would be likely if you have no prior contact with the criminal justice
system. You made one call and one stupid statement but she's made more and for that reason may do nothing. I don't see anything worse than probation coming of this for you under all of these circumstances (or for her, for that matter).
But just cool down and don't let her get you out of control, because that's a sure way to get yourself arrested which would be unfair, given that if there's a victim in this threesome, you're it. Now that she's been warned, if she keeps calling let the police warn her. And if she doesn't get it, let the police know that you want to press charges.
If she goes to the police, you'll know, because they will contact you. At that point, don't say anything about your argument with this woman at all. Just tell the police, like I said earlier, that you want to speak to a lawyer before talking to them about these facts. Then start looking for one, because you may need it.
I don't know how long ago this feud took place, but if it's already been a couple of days, it may be going nowhere. As she's married as well, that's another reason she may not want to make a big scandal out of this.