I Need Some Advice

 Good point. Great quote btw. 

How important is the big meal to you?  Is it worth postponing your surgery a week so that you still have two weeks pre-op diet?

It still leaves you 10 days to be bang on with your diet.  some people have the diet for 2 weeks prior, some have one.  The thinking is skewed but you already know that.  The one thing i would say is if you do it enjoy it.  Eating and feeling guilty or miserable are things you are trying to leave behind.

 I was on a two week liquid diet (low carb) pre-op.  I actually planned ahead knowing I had an important dinner right in the middle of the two weeks.  I started two days early.  I went to the dinner and enjoyed myself and actually ate much less than I would have any other time.  Twice on my pre-op diet I "cheated" with non-luquid food - and you know what - still lost 17 pounds.  The key is to not beat yourself up.  Keep moving forward.  One night out isn't going to derail you.  Now if this was happening 2 - 3 times a week that is different - but one night - go have fun and just think moderation!