What you are experiencing is extremely normal and expected. My assumption is that it is not lust related - rather a thirst for the warmth and intimacy of healthy marriage. Face it - there is an actual relationship. You have shared personal vulnerabilities, been mechazek each other, and look forward to becoming a couple - with the dream of having an atmosphere of shalom bayis and great kedusha - reminiscent of Adam and Chava before they were divided into 2 separate entities. 

It is advisable during an engagement to follow the guidelines of your community/rebbeim that minimize time spent with the kallah for this reason. (And other wise reasons).  When one has gedarim - dates and phone calls are not endless - it is less of a tease and easier to stay in control.

After all is said and done, your subconscious is going to cause your daydreams to head in that direction. As was advised by others, get busy with things that are meaningful and exciting to you that will overpower and distract. 

All in all, you are a hero and an inspiration for many guys here. You will b'ezras Hashem walk down to your chupa proud and peaceful, with none of the confusion, guilt, and warped ideas so many others get married with. You know why you are getting married and have rewired your brain about intimacy. Your chupa and future life will be enveloped in kedusha and therefore in simcha as well. To an extent - an angel among men.