She's been so excited for this wedding but she has zero respect for me. I think she cares about this wedding more for her own spotlight because she always mentions what she's going to wear and always brings the convo on what she's going to look like that day even through the dress search. I can't trust her to keep secrets. I was trying to be nice to her by bringing her to the dress appointments. I finally found my dress the other day and it's perfect and I ordered it. She knew through this whole process that I want it a secret from everyone, I reminded her so many times, I didn't want her to take pictures but she said "I won't show anyone". There was a small family gathering yesterday where she showed my grandparents and aunt and uncle and 1 or 2 others the dress -_- Also we're having a violinist for the ceremony and we decided to keep it secret, I was stupid for telling her that too (I thought maybe my mom would have some respect for my and FH's wedding) but yeah that's gonna go around. I know it's not that many people and they'll forget what it looks like by next year but I feel like she betrayed me and she is not going to change. I'm worried about who else she'll show, I'm gonna have to try and delete the photos, especially if it might reach my FH.
This wedding process is a lot of fun for us and hasn't been stressful on its own, she's the only stressful part of this and I don't know how to deal with such a stubborn narcissistic mother. She's a wildcard and I keep imagining some crazy thing she'll do the day of. She ruined my brother's graduation with a meltdown towards my dad, we begged her to stop for my brother's sake, so I'm worried she'd do the same at our wedding along with telling people everything... Christ

Re: I can't deal with my mom anymore
I think you've already figured out the best approach to dealing with her: don't volunteer any information, be vague when asked direct questions, and bean dip. We all have issues like this, and hopes that our family members will behave better than they normally do. But that really is expecting too much. Dealing with disappointment over and over again is no fun. I'm sorry
I feel your pain. I'm sorry.
I needed to rant... But yes I won't be telling her anything else, ugh. As I told my cousin, there apparently needs to be a -zilla in a wedding, in this case it's not the bride and I don't plan on being one, so she took the job, she's the only one stressing out causing everyone else to stress out and making issues out of things and causing drama, she's not even paying for the wedding at all and acts as if it's a bigger deal to her than us. I have to remind her, "Yes it's a big day for you because your daughter is getting married, but it's a bigger day for us, it's going to be one of the biggest days of our lives and we've been looking forward to it and working hard on this so please respect us enough to not do things like that".
My mother was a classic narcissist, and this book helped me a lot. I think it is what you need.
http://www.amazon.com/Will-Ever-Good-Enough-Narcissistic/dp/1439129436?ie=UTF8&keywords=when will i be good enough&qid=1464645394&ref_=sr_1_1&s=books&sr=1-1
My mother was completely uninterested in my wedding until she found HER dress. Then she couldn't wait to wear it so everyone could see her in it. She still had it 38 years later when I cleaned out her apartment.
So your Mom is more excited than you are for your wedding... You don't want her to share details... Stop sharing those details with her you don't want getting out. So you're having someone come in to play violin at your ceremony - GREAT! It's not like you're hiring a world famous touring violinist to come in, it's o.k. and won't ruin the "surprise". If anything, people will pay attention to the detail more. So your FI sees your dress - BIG DEAL! It's not the end of the world, and honestly, the chances of someone purposely showing him are pretty slim. Remind her that "No sharing means NO SHARING!" - and be firm, not squishy. (now if she's paying for said vendors - there's an added component but not addressing that right now)... While I understand your frustration, this sure beats what those are going through who have no one around them excited...
But I understand what you're saying. I'm already going to stop telling her things. And of course it's not the end of the world if my FH sees it but it's really important to both of us, he didn't even want to see the ideas I had for dresses. I took the precautions and removed all photos from my phone and put them into a folder in my computer, I made sure my mom has no photos and I asked my bridesmaids to delete their photos which they were ok with because they know I have a copy anyway. From the first dress appointment I didn't want anyone taking photos except from my own phone, but I'm too much of a pushover... I know looking back after the wedding I'd see how paranoid I was being, and I recognize that this isn't a big deal in the long run, but I guess the scare with my mom really started it.
The violinist thing isn't a big deal (especially if my mom told the truth), I come from a poor immigrant family that isn't used to this kind of stuff, so for them it'll be a nice surprise. It's not necessarily a "secret" but I rather guests not know every detail yet. Also she's not paying for anything as I mentioned. And yeah I know I'm lucky I have people that are excited for me but I wish she knew her boundaries. It's kinda like me and my FH are in a nice happy bubble planning and such, being excited and thinking about our future and she's a needle of stress occasionally hovering over. Anyway, now that the problem is solved I'm not going to think about dresses until it comes in 5 months, ha.
Also, I'd give your mom a heads up that if she plans on having a meltdown at your wedding like she did at brother's graduation, she will be escorted out.
Are there any relatives she likes to impress? Seat them with her or even ask them to stay by your mom's side for as much of the day as they can. If they know your mom, they will understand your request. I would happily do that for a relative on their wedding day to keep a potential "problem" guest from ruining the day for them.
I'm also going to ask her best friend to come earlier before the wedding so she can act appropriately and calm down and relax. Her best friend helps her realize when she's acting too crazy.
People will be happy and excited for your wedding (violin, your dress, any other details you have planned) even if they know ahead of time. Say Aunt Sally hears you're having a violinist she'll probably think "oh that's nice" and then move on. When the big day comes she'll be all "this violinist is wonderful @MCmeow did a wonderful job planning". No harm no foul that she knew in advance and it doesn't take away for the overall day. If keeping things a secret is that important, don't send people pictures/share details or be ok with them knowing and potentially mentioning it to other people, but trying to track down details or information that has "slipped" is a little extreme.
I agree to stop telling her anything she doesn't need to know. She has already proven she isn't trustworthy/ willing to listen to your requests, so don't keep trying to see if she'll "figure it out this time". If anything gets brought up by her, I'd be point blank with her. "Mom, I previously asked you not to share the photo of my dress to anyone, and yet you did. I will not share any further wedding details with you". "Mom, if you choose to act the way you did at brother's graduation, I will have you escorted out of the wedding".
Good idea to have her best friend around.
I know what you mean though about sharing details. My mom isn't a narcissist but sometimes gets easily worked up by stuff. When I had my wedding dress fiasco, she posted about it on FB- that really peeved me off for awhile. My thoughts were, it's my problem, and the whole world doesn't need to know about it, nor do I need to see the reminder of something that is currently permeating all my thoughts on FB. It was fine at the end of the day, and it didn't change anything, so I let it go!
If you're going to stress about keeping every detail a closely guarded secret, you're in for a long, stressful engagement. Personally, I'd recommend evaluating what is really worth the secrecy and relaxing about all the rest. If someone's enjoyment will be greatly enhanced by not knowing (ie your FI had expressed that he doesn't want to know and will be disappointed otherwise), then make the effort. If the surprise factor does not otherwise change your guests' enjoyment, then ask yourself if you're really doing it for them or for the attention you'll get for it. If it's the latter, then relax your grip on keeping it so guarded and save your energy for more important things.
It's fine not to want to share too many details about your wedding with others, but I think you're trying too hard to get surprise and excitement out of people. Your wedding will never be as important for other people as it is for you, and I think you're setting yourself up for disappointment if you expect everyone to be blown away by certain details.
Glad everything is better, @MCmeow!