They pushed a button. You still decided what happened after.

Provocation and response are two separate events. Someone can be entirely responsible for starting it and still not responsible for what you chose in the gap afterwards, however short that gap felt. The reaction was fast and it was still yours. That is unwelcome news and it is also the part that gives you somewhere to stand.

Notice the moment between the trigger and your reply, since it is longer than it feels. Practice one pause with the person who gets to you most. Name their part honestly and answer for your own separately.