I have heard that breakfast should be the big meal.... eat more at breakfast. Keep dried fruit for snacks, it still gives you the sugar you want/get from chocolate but it is a better kind of sugar. Try to have your carbs (rice, pasta) for lunch rather than dinner.
And talk to someone at the gym... that's what they're there for and you are paying for...

But I also know what its like to crave chocolate. I am wanting to lose 5 kg before october when we start TTC, but its hard.... If DH starts to tease you, tease him back - is he bigger than he used to be. Why not try to lose weight together....