Addicted to Diet Coke! Can I give it up?

I was also addicted to coke zero and totally understand what you are saying.  I also drank coffee regularly and have given that up too.  That happened about 4 months ago now.  I am pre-op but I was having nausea and vomiting and cutting them out helped a lot.  Yes, I had headaches at first and felt low energy, and sometimes still do, but I feel a lot better overall now and am happy I did it.  My advice would be to get a nice variety of sf drinks - the liquid ones are pretty handy and use lots of ice and make it all fancy so you do not feel deprived.  Also, there are tons of pre-made non-carbonated drinks now that are sf and readily available.  It will take some getting used to but better to make the switch now over time than to go cold turkey after surgery.  My current fave is vitamin water zero:

I was the same as you.  I drank diet coke from when I got up until I went to bed.  However on June 29, 2012 I went cold turkey and stopped.  I did it on the first day of a vacation.  My logic at the time was that I was out if my daily routine Siberia I was on vacation and that perhaps it would work for me.  It did.  And I haven't looked back since then.    Water is my drink if choice now. Usually with Mio in it.  Occasional Nestea zero and vitamin water zero for variety.  

Do it whatever way you can.  You honestly won't regret it in the long run. Might be difficult at first.  But this is just one step , of many,along a journey 

It is very easy to give up - I have given it up 100's of times.  In truth it is highly addictive and giving it up is very hard.  If I go back and have one just as a special treat I will soon be mainlining it again.

It is prominently displayed in attractive bottles at the checkout counter at most stores.  I have to constantly tell myself "NO".

I do drink Diet Ginger Ale and Diet 7Up sometimes, but most of the time it is plain cold water.

believe me you heath will be better if you try to wean yourself of it prior to surgery

...I gave up my (1) can of regular coke habit 6 months prior to surgery and never looked back.  I have to be honest and say I have tried a couple of gulps of Dr. pepper since my surgery almost 5 years ago and it HURTS so bad when you swallow...it's not worth it at all~!!

There are so many OTHER wonderful products that bariatric patients can drink..my favourite is Crystal LIght (tea) in the liquid format...just a couple of quirts into a glass with ice and voila..+ it's so small I keep one in my purse in a ziploc bag..also Vitamin waters as shown in a previous post come in so many wonder flavours~!!