If you haven't already done this, write down the reasons you want to lose weight. Then when you are feeling like the weight loss doesn't matter you can re read them. Maybe stick them up at your computer of on the fridge so you are constantly reminded.
For the most part I could tell the world to go hang where my weight was concerned which is why it took so long for me to do anything. Photos were the big thing for me I would always just stare and them and think I am huge why doesn't anybody say anything. And realising no matter how many times I tried the BMI calculator it wasn't going to stop saying obese until I chose to do something about it! I have my reasons written out and I keep some earlier photos handy to remind me what I no longer want to look like and why I am putting in this effort.
Just some suggestions that may or may not work.
Good luck with the city to surf too.