Frustrated

If your goal is to cut the calories without suffering from caffeine withdrawals, the solution is probably diet soda. OR drink one soda, then drink a non-soda drink (like maybe water or tea). Like, force yourself to switch back and forth. I personally kicked my daily soda habit via iced tea, and then hot tea.

How many ounces/ml of soda do you drink? Coffee has something like 4x the caffeine as soda (depending on the coffee and soda.)

I never had a soda addiction but i love my coffee. Anyway I have experienced diet related headaches before and learnt that the problem is getting body salts out of whack. This might actually be part of the problem you've got. To see if that is the case, try going without your soda but having a salty soup at least once a day. This will make you drink more water too.

When you salts get out of whack, you can end up dehydrated and this what causes the headaches. I do not believe stopping sugar causes headaches since i used eat a ton of sugar and never got headaches when i stopped suddenly. I have done it many times and never had headaches.

I am not sure if caffeine is the cause of the headaches because while i drink a lot of coffee i've never had withdrawals from stopping caffeine either.

I really think the key may be in the salt issue. So whenever you get a headache, try drinking a cup a soup or a miso soup or if you were australian, i'd say vegemite tea. If its a salt issue, the headache will pass very soon. Keep your water up.

If you want to continue having sweetness, then I think you will always have problems of one type or another. I do not believe replacing sugar with artificial sweeteners is a good long term solution for weight loss or anything else. So i would not recommend replacing soda with diet soda until at least you've tested my theory about salt and can't find anything else.

Personally i think you should take up eating fresh fruit instead of soda.

I drink a coffee in the morning for the caffeine, Then I seltzer water for the carbonation. I don't care for the aftertaste in diet soda.

Then don't stop drinking them.

Drink a little less every day until it's none.

The other option is to go cold turkey and deal with the headaches. I've found that being outside is helpful and a lot of swimming is even more helpful.

Getting off caffeine isn't as hard as heroin. You can do it on your own.

Maybe iced tea? It sounds like you want a colder drink. You could drink iced tea either unsweetened, or try Stevia or the like to add, many say that it tastes less chemical-ey than the sweeteners found in diet soda.