Does anyone else feel angry all the time?

I have recently cut ties with my family, as well as many members of the extended family (the ones I consider "toxic").
Though this has brought a REALLY healthy change in my life and I feel more empowered and myself than ever, my emotions went completely out of control these last months!

My partner is getting the full load. Where I am usually SO good in controlling my emotions, they are suddenly coming out in very CHILDISH ways. I can't remember ever having had a tantrum in my life.

Now I have a tantrum nearly every week!

What is wrong with me? Why am I having these anger attacks, even though my life has changed for the better after the loss of abusive family members?