am I wrong for getting mad?

So my child's father is a complete piece of shit and isn't wanting to be involved in the babies life. At first his parents wanted me to give the baby up for adoption but they've came along and decided that they wanted to have a part in the babies life.. I said okay. Well I have a boyfriend now that is amazing and that I love to death.. his father was okay with the situation but then I found out his father knew my child's grandpa. He went by my babies grandpas business to discuss business but somehow I was brought up. The grandpa started saying a lot of bad stuff about me and made it seem like I was terrible.. yet he didn't bother to mention how the dad left me out of no where and screwed another girl 5 days later. I haven't done anything wrong and I was made the bad guy.. am I wrong for flipping out?