someone called my wife a slur in a club and i froze instead of swinging

this is eating me alive. wife is mixed race and the most beautiful woman in any room she walks into. club in toronto, single bloke approaches, she politely declines, he walks off and mutters something racist loud enough that we both heard it. i just... stood there. didnt move. didnt speak. my wife looked at me and i could see in her face the exact moment something between us changed. by the time my brain caught up he was gone. weve barely spoken about it. its been ten days. how do i come back from a freeze like that. im her husband i should have been over there. 47 shes 44 weve been doing this seven years and i've never failed her like that before