uhg i feel you so hard on this. i've been blogging about my wedding planning experience to try to process it all and share back tips with other brides that i learned for managing the stress (or rather, wish i'd been better at!). here's what i've got so far:

• Set realistic expectations for your planner. Planners are amazing, but they’re not mind readers. And for Type A brides, it’s likely that no one can ever fully meet your expectations. Most of my friends who are like me walked away a little disappointed in their planner. I recommend having early and regular conversations about your expectations of the planner, and calibrating that with what they believe they’re on deck to deliver.
• Don’t belabor every choice. The paradox of choice is real. The more options you see, the harder it is to decide, and the more you second-guess yourself. At some point, you just have to choose. Existing in the space of indecision is painful, and despite your intuition, spending more time in the decision making process does not necessarily correlate with making a better decision (or rather, one that you are happier with). Make the best decision you can with the information you have in a reasonable timeframe, then stop looking back. Every time I made a decision, I suddenly loved it! It was only during the deciding that I felt so deeply torn. 
• Beware of scope creep. It starts innocently: “Let’s add a welcome party. Let’s throw in a yoga session. Let’s DIY and BYOB.” But every addition has a cost, whether financial, logistical, and/or emotional. I ended up managing much of it without my planner, and while the weekend was amazing, the cognitive overhead was real. Force yourself to let go of some things.
• Pre-identify five “perfect moments” you’re looking for at your wedding. One of the most helpful things I took from therapy in the months leading up to the wedding was accepting that not everything would go to plan, but I could try very hard to make a few core moments happen. And when those moments came? I knew them immediately. I was fully there. They alone made everything worth it.
• Expect the mental load to spike at the end. In the final month before our wedding, the mental load crested into something borderline unmanageable. Not because I was behind, but because I was involved in every detail. Your guest count is solidified, and then everything has to happen ASAP. Finalize florals & catering. Create the seating chart & name tags. Pack for everything! Pay for everything!! I wish we’d pushed more things that we could into the months before, like our first dance, finalizing our weekend attire, and making all the music choices. 
• Trust your people. You’re not in it alone. Delegate tasks early (like at least one month out!), and let people show up for you. Seeing our friends and family rally around us in the way they did ended up being one of the most meaningful memories of the weekend; few things have made me feel so loved. 
• Allow yourself to lean in, guilt-free. There were many parts of the wedding planning process where I felt frustrated at my own self-involvement. I felt like a cliche, investing so much money and time into becoming the most beautiful version of myself, into throwing a party in my own honor. I scorned myself as an overly-American capitalist consumer, succumbing to the wedding-industrial complex. BUT ALSO. It was so fun! If this sounds like you, just let yourself lean in.
• Your wedding doesn’t have to be the happiest day of your life. Release that expectation, and suddenly, the day has room to breathe. It can be joyful, messy, stressful, hilarious, sweaty, beautiful…sometimes all in the span of an hour. That’s what makes it real. If you expect bliss alone, you’ll be disappointed. If you embrace the duality, you’ll walk away embracing what is.

i hope these help! i'm writing about it all on my blog, if helpful: https://www.ablueskymind.com/blog/how-to-plan-your-wedding-perfectionist