Planning a wedding is no joke-- it's time consuming, often overwhelming and stressful. Add in the peanut gallery's opinions, input and 'advice' on what you should be doing and how you should be doing it and it's enough to drive a girl to drink! Don't stress. Manage the input without losing your mind.
-Just smile and nod. The easiest way to deal with unsolicited advice is just to ignore it! Smile, nod and go about your life unaffected.
-Tell 'em to can it! (Politely!) When someone starts in with the 'do ya want my opinion?!' Politely cut them off with 'no thank you!'. You don't have to listen to anyone, and what does that lady at the grocery store really know, anyway?
-Stick to your guns! Seriously, you made the decisions you did for a reason. Don't let yourself be talked out of something or start second guessing yourself. You'll be happier if you stick with your plan and aren't easily swayed.
-Trust your pros. They know what they're talking about way more than Great Aunt Mildred, even if she doesn't think so. Tell her not to worry-- you hired someone for that.
-When all else fails...If someone still isn't getting the hint, just smile and say "Hm. Interesting. Thanks. Lots of think about." Eventually, they'll figure out you're not actually listening anymore.