Am I the asshole for punching my husband's sister?

Am I the asshole for punching my husband's sister? I, 32, and my husband, 34, let's call him Hyde, have been married for 6 years. We have a 3-year-old son together. Let's call him Ben. Our relationship has always been strong and filled with trust. I have never had any problems with his family before, and my family absolutely adores him. His sister, 28, and I have always gotten along great. When I was pregnant with our son, Ben, she started acting strange. She was always offering to help my husband with everything having to do with our son, but when it came to me, it was radio silence. I assumed she didn't want to upset me by any chance since my hormones were all over the place. Once Ben was born, she was an amazing aunt. She was always asking my husband Hyde to watch Ben and even keep him overnight. To be honest, the break was nice sometimes. However, when Ben turned 3, my sister-in-law started inviting only my husband and son to activities and intentionally excluding me by picking days when I couldn't attend or by only 3 tickets. She even claimed it was for brother and sister time sometimes. My husband started noticing that she never asked me to go out with him anymore and brought it to my attention several times. I brushed it off at first, but a few months later, I told him that it was very hurtful for me. The next time his sister invited him somewhere, Hyde responded that he would not be going if I was not invited. This is where she flipped. She started blowing up his phone and telling him that I do not need to be involved in everything and that they should be able to have sibling bonding time with her nephew included. He eventually blocked her to avoid her bombarding and let her cool down and I went ahead and did the same before she started with me. About an hour later, she showed up at our front door with their parents. Ben was in bed, so we stepped outside with the baby monitor in hand to avoid disturbance. She then started going on and on that she is Hyde's immediate family, how she should be a priority over me, and that Hyde would never love me like he loved her, which I hope not since she is his sister and not his wife. I didn't pay much mind to it until she said something like, I'm the mother that Ben will never have because you're here. I will love Ben more than you could, and I love Hyde more than you ever could. The look on my husband's face was pure rage. I admit I shouldn't have done this, but I saw red in that moment and punched her in the face. I heard a crack in her nose, and she started crying. My husband and my father-in-law are completely on my side. My father-in-law even says it sounds like she has feelings for Hyde. However, my mother-in-law says that I was out of line, and she only meant it in an overprotective sister way. It's been two weeks since we spoke, to his sister or mom, and I'm starting to feel guilty about it. My husband has heard from my father-in-law that her nose is fine, nothing is broken, and she's not pressing charges. But my sister-in-law doesn't think anything she said was wrong. So am I the asshole?