When FH and I got engaged it was week before my moms birthday. When we went to her birthday party and announced it to my family members who came in from out of town my sister got upset. FH and I were discussing the time frame we were looking at regarding planning and setting a date when she came back into the room with a small package. She pulled out a couple of rings and stated that they were hers and her boyfriends engagement rings that would be used when it was official.
This previous Sunday I was again at my moms talking to her about a bridal show coming up and what day and time we can go to it. My sister came in and joined the conversation asking if my wedding was going to be fancy or not. She then told me that I should just go to a court house and have the wedding there because that is what her and her boyfriend were going to do over Christmas break but the marriage license would've taken too long. This was said in front of my mom which to me is disrespectful, I know my mom wants to see both of us get married.
My sister has always had this problem where if she is not the center of attention she makes everyone miserable or does something to make sure she is. I never got along with her and I do not see our relationship improving in the future. FH and I decided together that we did not want her at our wedding and if someone brings her anyway that they can leave with her. Is this too harsh? Should I invite her anyways despite knowing that there is a good chance she will try her best to ruin it?