I can's stand my sister in law and MIL! Help!?

I am a newlywed who got married 3 weeks ago, and have been living with my husband for 2 years prior. My husbands family has always been manipulative, know it all's. I learned to ignore this for the sake of my husband until recently. When we announced our engagement 4 months ago, they got pretty bad. My MIL and SIL and FIL tried completely to organize my wedding, from the colors I chose to the location and food. When we told them we were having our reception at my sisters backyard his dad started yelling at us and telling us NO! NO! NO! That it was to far from where they live and to small that we needed to invite ALL of his family and they were going to look for banquet halls for us or better yet have the reception in their backyard. They threaten us not help us if we had the reception there. I of course did not allow it. His sister called saying she found our center pieces and that it was red cos my colors, brown and pink, were to lifeless for a wedding "l'll be there in 20 min w/ mom to show you" she said. Then she went on about how a woman belongs in the kitchen, that my husband shouldn't be cooking and if I really loved him like I said I do I would wake up every morning to make him breakfast at 6:00 am just like she does to her husband. I stayed quiet. Then she went on about how she had a catholic wedding, and in the eyes of god and the family she left her house a good woman. That GOD look good on her marriage. She said this since me and my husband had chosen to have a civil ceremony. My MIL looking at her w/ affection and proud her daughter spoke up. I stayed quiet. The wedding came and they caused their drama but it was MY day so I ignored them and had a blast. It wasn't till the day after how everyone told me all the things my SIL did that got me fired and finally saying ENOUGH! All these things I had went through were between my mom and I so my family who came from out of the country and state did't know. She was so rude that she made herself stand out. At my wedding I got a tad bit tipsy and didn't see or hear all these things. She forbade everyone from taking the centerpieces even after I told my friends and fam they could take them. IDK why. She ignored my 81 year grandpa when he asked for cake cos she decided she should p it out, along with the waitresses. He took out his hand to receive the piece and she simply turned around and left to give it to someone else. She told my mom the same thing about getting married catholic and leaving her home a good woman as if my mother would agree with her. Mu mother simply turned around and left her talking to herself. She pushed me when I threw the bouquet to catch it even though she is already married and so on. A day after we got married they wanted to come over to look at all the presents we got and got upset we opened them without them being there. At this point I was fuming mad about everything and how dare she just come to my house as if nothing happened and I'm to be nice to her. When they got there, I went upstairs and Ignored all of them until they left. Well, my SIL calls my husband to make invite us to a late mothers day dinner at her house tomorrow. I am so angry and upset still, I don't want to go. They can be so rude to my family but I am expected to be whatever? Should I go for the sake of my husband or just not go and show them I will not be made a fool of. I know if I go there mother/daughter comments will start and this dinner is more of a dread than anything else. My husband tells me I should be the bigger person and go but I don't agree! Please help, what should I do?