I'm sorry to hear that your mother is acting the way that she is. You just need to sit down with her and try to explain to her that what she's doing or rather what she's acting like is really hurting and upsetting you and that you'd really like her to be apart of this wonderful occasion but if she can't get over what's bothering her with your FH or whatever it is then also explain to her that she won't be apart of your life or her future grandchildrens' lives because you don't want to put your future family in any "war zones" so to speak after you get married. I think she just needs to accept the fact that you are getting married and that there's nothing she can do about it. Hope my input helps in some small way and have a great time with your wedding planning!