my ds1 was 21 months, and ds2 was 3 months when i got rid of there dummies. i had to stay at my dads for a few weeks, and when it was time to go home, i accidently left all of them behind, ds1 started asking for them, i told him that pop wanted them, he wanted to go to the shop and get more, i told him they had stoped selling them while we were away. it was hard for a week or 2, but after that they were fine and adjusted to not having them anymore. (if only there bottles had been that easy!)
good luck, hope you find a way that works!