Your not alone, i didn't sleep for months until i had chosen the resort. I was crying, stressing, second guessing every decision, constantly changing my mind.
I would definately recomend getting a TA. they can answer your questions about the resorts (i'm sure they have seen most of them) and they can help your guests with any questions they might have.
Well at least you narrowed down some of your choices with the priorities, now i would start making a list of other priorities that may be important to you like swimmable beach, restuarant choices, near airport, and if you picked a price range that should narrow down your choices by a lot. when you talk to a ta if you give them a price range per guest i'm sure they can give you some resort choices.
Don't get too upset, picking a resort is by far the hardest decision you'll have to make.