I don't have kids, but a very good friend was in a similar situation with her child/sibling/FOO last summer.
Back then my friend was mainly concerned about the impact that her "moodswings" and parenting patterns could have on her little one and sought out an "attachment parenting" group. Turned out she loved it, as it helped her to form an even better relationship with her kid, but also work on her childhood experiences. Not sure if it was a coincidence, but quite a few parents in her group were raised in more or less dysfunctional families as well...
Maybe such a group would be worth looking into for you ? - I think it's great that you notice changes / a pattern in your life and actively look for help and input instead of falling back into "old" acoa patterns.