maybe a good boundary for you could have something to do with how you will allow people to treat you? sometimes we have to take a giant step back and see this isn't about where you parked, or how you reacted to how he reacted but that his behavior was completely out of line, disrespectful and verbally abusive.
we teach people how to treat us. somehow it's become "ok" for him to call you vile things and then turn around and say it's your fault. imagine how nice life would be without that type of negative draining energy???