Wedding troubles

its long but I need help.

I really don’t know what to do right now. I’m in a tough position. My fiancé is in a different state right now in the army. He comes back next month and then again in September when our wedding is taking place. So far I have the venue, bridesmaids dresses, my dress, photographer, and some decor ideas started. Invited get sent out next week. So here’s where the problem comes in. His mom has been slowly trying to take over. First it started with the guest list. We had a set list of 160 people. I sent her the finalized list and asked her to send me all of the addresses from their side of the family. As I was making invites I noticed a lot of the addresses she was sending me, weren’t on the list and it was clear she was adding people. I hinted to her that they weren’t on the list and she asked me to add them, so I did. Once I was done with all the invites she sent me ANOTHER small list of people to add and to make her happy, I added them. (Mind you my parents are paying for everything). So guest list is done and we’re at a total of 200 people...

So here comes the next issue. She was rude at my dress appointment. She sat on her phone with her daughter the whole time. Which is fine. The part I had an issue with was her daughter was sitting on speaker talking about her doctors appointments and how much she hates where she’s living currently all while I’m trying on wedding dresses. Maybe I’m being selfish but I felt like that time was my time and she was being rude.

Another issue... She’s being very controlling as far as decor goes. She wants the drinks set up a certain way when I already have a plan for that. She wants table decor to be the way she likes them. She wants me to use all of her sister in laws decor which is fine. But every time I would say I didn’t necessarily like something she would tell me I was being rude. Ok I’m sorry but if it’s MY wedding shouldn’t I be able to say what I like and don’t like?

This whole situation has stressed me out tremendously. My fiancé is very understanding of why I’m upset and has told his mom a few times to back off on certain things. I don’t want to cut her out of helping me with everything and I don’t want to be rude but I don’t know what the hell to do at this point.

Any tips and advice would be greatly appreciated.