Nice one dude,
The key is to just get straight back on your bike if you fall off, and to allow yourself a treat every now and then. I'll still have 5 or 6 drinks in a night, I just won't do it very often. The key is to eat well 90% of the time and get some good exercise. I started on the 17th of jan, and as of this morning it's been 10 weeks and I've lost 18.3kg. Starting weight of 157.6, and I'm currently 139.3.
I started a blog when I hit rock bottom, and have updated it each week. Check it out if you're interested: http://lifecangetyoudown.blogspot.com/
Motivation helps me a lot. I'm doing it with 2 mates. our initial goal was to lose 15% bodyweight by June 30. The first person who reaches the goal receives $500 each from the other 2. The 2nd person who reaches the goal also receives $500 each from the other 2. And likewise if the third person reaches the goal in time, they receive $500 each from the other 2. So if we all reach our goal, which is the desired outcome, we all break even. But if you don't meet the goal and the other 2 do, you're up for $1000. Good motivation
Ive also got a wedding in August so that helps. Find something you want and don't let go of it.
As for diet, I can happily eat the same thing day in, day out. Breakfast is 2 slices multigrain toast with vegemite. Lunch = Double cut wholegrain roll with light cream cheese, turkey, red onion, roasted capsicum, baby spinach, salt and pepper and mustard. Dinner is 2 chicken thighs marinated in various sauces (~200g), 4 carrots and 1 bunch f broccolini boiled, with tomato and bbq sauce. Add to that a few cups of green tea, and that's all I have. If I have to go out for tea, I try and pick something that doesn't look so bad, but I don't deprive myself. I don't have a beer for the hell of it, but I don't deprive myself from going to the pub on a friday after work. You have to still do these things, but as long as you're not doing it all the time, and the next morning you get back on the healthy eating, you're going to get to your goal.
I still have a crapload of weight to lose, my goal is 80kg from 157.6, but as long as I can just keep on keeping on, even if I slip every now and then, I know I'm going to make it.
Also when people start making comments about how well you're doing, it does wonders for motivation.