Parker80

You may want to consider starting to change some of your habits as soon as you can, like reducing/eliminating alcohol, sugar, caffiene, nicotine or anything prohibited in the prep for surgery so you are ready, willing and able to transition.
Studies show it takes an average of 66 days to build new habits, and it's often a bell curve.
Get feedback from the Team you choose and follow their instructions.
Safe Journey ?
Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40, 998-1009. (http://onlinelibrary.wiley.com/doi/10.1002/ejsp.674/abstract)

I typically have a glass of wine before dinner. Should I completely stop before starting on this journey? I go for a consultation for weight loss surgery next week.

Different programs have different rules. I didn't have to stop at the beginning of the program, but my doc does not want us having alcohol after surgery during the rapid weight loss phase (he'd prefer not ever, but he's realistic). Both because of the empty calories, but also because of something I don't completely understand about the liver - that the liver is busy dealing with the weight loss - and we metabolizing alcohol differently after surgery. I haven't really asked because it wasn't that important to me. I'd eventually like to have a glass of wine every now and again, like on my birthday, but I'm not worried about it now.

It may be good to taper off before surgery, but its worth talking about with your surgeon.