I totally get you - i have a round face and glasses which shrink my eyes, and i've added a covid stone to my menopause stone.
Things that might help are to put your hair up, my 'up-dos' tend to be messy with a hair clip but i think it balances out my face. Flowing hair can be hard to pull off if not willowy, and you hair will still look fantastic if it's up, or half up and down.
Maybe dress down your wedding dress a bit, so you feel less like you're playing dress up - something simple like a cropped cardigan or a bolero could make you feel more like you.
Try a few make-up looks in department store beauty sections - or even a Boots. Go when it's quiet and tell the consultant that you want to try new, subtle looks, so you can get an idea of whats possible. Blusher is also a mystery to me - my roundy cheeks are naturally pink anyway and i'd be worried that any attemot to contour my face would rub off weirdly and i'd look mishapen.
But you could get ideas for different eye make ups to make you happier with how they look, and maybe try different lipstick shades too.
And unless you won't fit into your dress i really wouldn't bother with a crash diet - you're under enough stress already and you'd have to get the dress altered.
Photos can be a pain - have a selfie session and see what angles you prefer - slightly sideways face but looking at the camera etc. And ask your photographer for advice - you only need a couple of decent ones really for your/his parents and you to frame. Your can use your husband for camoflage, have photos with you looking up if he's taller etc. Don't order prints of any you don't like, and try not to worry about how you look in photos taken by friends and family, sure they'll more than likely stay on their phones and never be looked at again.
And finally, and i know you're sick of hearing it, every bride looks lovely on her wedding day in the eyes of the people who love her, so thats your husband to be, your family and friends, and really should be you too!
Have a great day!