I understand how you feel. The idea of the band not working is scary. But the way I see it it is better to try SOMETHING than nothing. I am just speaking from my experiences. I don't have the band yet but will have it next Thursday. I'm on day 5 of my preop. I get 3 protein shakes a day and a healthy choice meal for dinner and other sugar free/fat free liquids. It sucks but I'm doing it.
With that said, only you can decide if you're ready for it. If you can't make yourself do the liquid diet that isn't a great sign really. Sure I'd love to sit down to a great big buffet of calories and fat right now and screw up my diet but I want to be thin MORE than I want to eat!!! It's more important to me, so I'm willing to make that sacrifice. And you really have to decide that this is more important to you than food is before you go in to this, especially if you are an emotional eater. Some people end up "mourning" the loss of their comfort foods. But I think the successful people are able to focus on the positive aspects of getting the band (being thinner) instead of the negatives (giving up eating all you want).
Do some soul searching and you'll get your answer.