Don't beat yourself up----
Something is triggering this reaction---it needs to be explored and de-mystified. If you have a t. it is a perfect opportunity to work this out, if not it might help to note what else is going on when you have these thoughts/feelings/reactions; you may find a common denominator (eg: are you triggered into the past? does something in the relationship remind you of times you felt afraid/angry/helpless?...are there words?)
It can also help if you can (not easy) have something you do when these feelings/thoughts come on (take a run/walk/bake bread/make something/...)
And, be honest with the boyfriend if you do trust him.
But, don't let everything that is "wrong" be your fault either.
((((((((((((((((((((big hug)))))))))))))))))))