I don't know how old your kids are-but if they are old enough to get out of the car and walk to your door-let them. If they are small-tell your ex to walk them to the door and if the bf gets out of the car-you will call the law and file a restraining order.

I know none of that changes how you feel. But try not to 'feel' just deal with what is necessary-and only that. No small talk, no arguing, you don't even have to look at her-nothing. Use 'NO CONTACT'.