I hear you.. Go to GNC and go to the refridgerator in there and get the Isopure CLEAR protein drinks. It's like drinking water consistency... and they have flavors like Apple Melon and Blue Razberry.. I like the Apple Melon the best.. it tastes like a jolly rancher.. and its not that thick shake crap.. each bottle has 40G of protein. They are slightly expensive.. about 4.50 for a large bottle, but I would drink half the bottle in the morning and the other half at night. You can also do the LOW CARB Slimfast shakes. It also has 40G of protein with low carbs and sugars. You can get a 4 pack for like 5 or 6 bucks. And it doesn't taste bad.
Sorry you are stuck doing that damned liquid pre-op diet. I wish some doctors weren't brainwashed into thinking that's what they have to do. If you get to the point you simply have to eat something, just eat a can of tuna.... you'll be fine. Sorry, it just irritates me that people are forced to do these stupid liquid diets when you can do the South Beach diet and get the same results...

oh, and not starve... and learn to eat properly.. gee... what a good concept!! sadly, a lot of the liquid dieters run out and have a damned cheeseburger because they can't help it anymore.. so, if you get to that point.. chicken or tuna and that will help out and your liver will still shrink and all that.. Good luck!