If dieting is a struggle try tackling it from the healthy eating point of view, aim more for what you should be eating rather than what you should be cutting out.
Have a look at portion size, don't deny yourself the food just have a reasonable size poetion rather than a plate piled high or a whole family bag of maltesers.
It does help to plan menus, but plan proper meals for the whole family not just a diet meal for you, much more likely to keep at it and good for everyone too. I find my last minute nothing in the cupboard meals atre my rubbish unhealthy ones, if you plan you can ensure you have enough veggies and fruit in for all your meals.
If you feel the urge to snack, drink a glass of water and see if that will do you for a while, helps to drink loads of water anyway and sometimes when its not real hunger the water can satisfy you for another 10mins at least .
Walk, walk, walk great destresser too, after lunch stroll at work (can help to escape for a bit if you have time), if the LO is still in a buggy get out and about and walk as often as you can, easier to fit in than the gym and you can take the LO too.