Surgery tomorrow..too late to back out?

EDIT: here is an update! I ended up going through with it. Although it's day 1, I'm really excited to start my new life. https://www.reddit.com/r/gastricsleeve/comments/1istm6y/update_surgery_tomorrowtoo_late_to_back_out/?utm_source=share&utm_medium=mweb3x&utm_name=mweb3xcss&utm_term=1&utm_content=share_button

As the title says, I am supposed to be getting surgery tomorrow but I am freaking out. I was pretty confident in this decision until I had a date. The last few weeks I've been a roller coaster. This week, I've been feeling at peace with getting the surgery but here I am the day before and I don't know that I want to do this anymore. I have been doing good on the liver shrinking diet. I wonder if I just put more effort into dieting is this necessary? I keep thinking of why I want to do this; to be a better mom and feel better about myself but I don't know that I want to remove so much of my stomach forever. What if something happens down the line where I need more stomach removed? Will I just have no stomach?! Everyone keeps saying I'm not "that" big. And I know that, but everything I've tried before doesn't work. I feel like the thought of this drastic measure might motivate me to actually make a change in my life. I know people can't decide for me, but what are your real thoughts? My husband is supportive either way. My endo (I have PCOS and Hashimoto's) thinks I should not. Maybe I should listen?