Ok, so a little shallow BG first, then our decision, and finally the email I've drafted.
BG: My mom is a negative, manipulative person. Probably a narcissist. Until I got pregnant and stumbled upon this board, I've either stood up for myself and let her sweep it under the rug after a few months, or just let it go and put up with it because I know she'll never change, and I'd gotten sick of fighting. THEN, I got pregnant with our little squishy. She was a surprise, but we're so excited. My mom said some WTF things... she cried herself sick after she got off the phone with me when I told her the news because she couldn't believe I was ruining my life. I'm an adult, we've been married for 2.5 years, together for 4, he has a good job, and we've always wanted kids and always intended on having them so... WTF? According to her having all of us kids (there's 6 of us) ruined her life and her life is basically over now, so that means having kids will ruin my life too. Oh, and then there was the gem of her telling my sisters she'd pay for my birth control or for me to get my tubes tied after this baby because SHE doesn't want me to have any more kids. And of course, the best, she's trying so hard to be happy for me and my DH. 
Unfortunately, most of this stuff I just blew off at first. Then came her demands of who would or would not (my dad's fiancee) be invited to both my baby shower (which was not even planned yet) and my child's birth. Both of which I just ignored at first. There's some miscellaneous shit from her and then she finds out that my dad's fiancee has been invited to the baby shower that my AILs are throwing for me (to which she was invited), and even though dad's fiancee is not coming, Mom freaks out, rants about my in-laws trying to "take over" (they're not) and refuses to come to shower. Cue me ignoring her from then out. (BTW, parents have been divorced for a few years now, and she's been dating someone since before their divorce was finalized. She's the one who cheated and left him)
FF a few weeks we find out that I'm at risk for pre-term labor (softened and thinning cervix as well as frequent contractions), and stress is the last thing I need. Good thing I've ignored my mom and her crazy texts the past weeks, right? Thing is when our squishy does come, we plan on calling our parents and siblings to let them visit the next day in the hospital. However, I do not want my mom there. She is on a TO until she can apologize, but I have not told her that, as contact with her stresses me out and the most important thing right now is keeping me and squishy safe. I am afraid that she will show up with my minor siblings at the hospital and either pretend everything's peachy keen, or get a bit nasty... it could go either way with her. So DH and I decided to email her now to make things crystal clear. I've drafted up the following email.
Mom,
This is to be clear on why I am not currently responding to you, what our expectations are for the birth of our daughter, and our relationship with you going forward. First, I have decided to take a break from interacting with you until you have had time to formulate an apology for your behavior and what you’ve said regarding me and my pregnancy, my baby shower, and my family who was generous enough to throw my baby shower or help to organize it. Regardless of whether or not you are ready to apologize earlier, I will not be ready to deal with this until after the birth of our child and my recovery. This is not up for debate or discussion.
Second, when my child is born, I will be calling my siblings to let them know and invite them to come see her. I am aware they may not be able to come, depending on whether or not they have school. However, this invitation does not extend to you. If you disregard our wishes, you will be asked to leave immediately.
Lastly, none of this is up for debate or discussion. Any attempt at an argument, questions, or contacting me in any negative way will be ignored.
What do you lovely ladies think? Anything I should add or change?