I know just how you feel. I just told my remaining family off, basically just like you did.
To make along story short, I told my Dad off in 1999 when he decided my then BIL was more important to him than his son, and proceeded to tell me, "Don't do anything to stop him from getting on where you work" and "Don't do anything to effect his career"; this after he nearly destroyed my career at another place we worked at (another one of "Daddy's Great Ideas"). Well, everything went to crap, and I left him and that job. I became the bad guy for leaving, and stating why to the employer. My BIL kept up with discrimination, harassment, defamation, and slander of me at the new place. I quit, and he was fired soon afterward. Again. my fault.
My Dad passed in 2006. I did not go to the funeral. Only my one sister knew the truth as to why. She made up an excuse as to why I did not go. Other family members were saying lies about why I did not go, and they still, to this day, lie about it.
Last year, that one sister, the only family member I respected and respected me back, passed away. My family then decided that I was the ONLY family member to not speak at the funeral, as, and I quote, "Everybody else will say everything about her, you will just be repeating things again." Well, I bypassed them, and when my brother tried to come up and remove me from the podium, I yelled, "And here comes the toxic control enforcer to stop me. But he does not know about my sister and I and this, that, and another thing that many people here may remember, but NO ONE ELSE knows about." My brother and I have not spoke since. My living sister has disowned me (the feeling is mutual), and my Mother was put in her place about the whole situation, as she was a major contributor to my brother and living sister's actions.
SO, long story short, I have told my remaining family off for their toxic control of me, and if they want to get back together again, they will have to follow MY rules from this point forward, which include mutual respect of each other. To date, only my Mother has signed the agreement, made her peace with me, and has done her best to treat me with the respect she would like to be treated with.
I agree wholly with what you did. Don't feel that you are a petty person or a bad person. Sometimes you just have to take the bull with diarrhea by the tail and face the situation, just like you and I did. Yes, you may feel like crap for doing what you did, but that feeling will soon pass. BELIEVE ME, not having to feel like you are trying to tap dance in a mine filed at family gatherings because you might trigger one of those poor family members that think they are better than you are is as freeing as a draft horse losing its harness and no longer pulling a heavy wagon.