Sponge a bit more info as promised. The book I mentioned is still available, the one I followed is called the Carbohydrate Addicts' Lifespan Programme (please ignore cheesy Americanisms!), by Richard and Rachael Heller. The basic principle is to eat low-carb for most of the day, following quite restricted food lists, but one hour in 24 is 'reward meal' hour where you can eat a meal which balances carbs, protein and veg (hence my daily chocolate). I found it really manageable to follow.
It worked wonders for me when nothing else did, but you would need to check with your consultant how it would affect your TTC. I was extremely surprised how much it affected my milk supply, but the principle of the diet is based on insulin control, so it must have an effect on the whole endocrine system I suppose. Looking back, I now wonder whether our difficulties ttc ds might have been linked to the way I was eating. Guess I will never know!
If it isn't suitable, the Hellers have also written a step-by-step version called 'Healthy for Life' where you gradually build up in babysteps and develop control of your insulin levels and food cravings that way, but I have never got this to work for me. Without the craving control of the full version, I don't really have the capacity to choose my foods at all (said through a mouthful of mince pie that i don't think i even wanted )
If interested you can usually get all their books cheap on Amazon used.