Cutting out diet sodas...

I am going to attempt to cut out diet coke. I am an addict! I love the stuff and typically drink 2 cans per day (in addition to drinking 60 ounces of water each day). I have been known to choose a diet coke for dessert instead of cookies, brownies, or cupcakes! That seemed to be a better choice, too. Now that my hubby and I are TTC, I think this no longer wise! I know the caffeine is not good for TTC (or after conception) and the aspartame is "the devil" when it comes to overall health. I have a hard time resisting it though. Any tips for dealing with cravings? Caffeine headaches? Healthier alernatives? Motivation or encouragement?