Cutting out energy drinks doesn't have to mean cutting out caffeine — it just means finding a different way to get it.
Tapering down gradually rather than stopping cold tends to be easier, since your body has adjusted to a certain amount and dropping it suddenly can leave you feeling worse for a few days.
Swapping in a smaller, sugar-free format for at least some of your usual cans is one way to taper without losing the caffeine altogether — you control the amount more precisely than with a full can.
Neuchu gives you 50mg of natural caffeine per piece, sugar-free, so you can dial the amount up or down as you adjust. You can find it here.