So you and Jezzie finish a 6000 calorie cake in 2 days? That's 3000 cals each per day just from cake......that's way more than the amount of cals you are posting about eating. Even at 3 days, that 2000 cals each......something doesn't add up. 
It works like this:
Say we bake a cake at 9 PM on Monday. Right after baking, we each eat a Slice at about 11 PM (cake has to cool hence the 2 hour wait)
Tuesday Morning at 8 or 9 AM: We each have a slice of Cake for Breakfast- At this point the cake is half gone as there are only 4 pieces left and the cake is not even 1 day old.
Wednesday Morning at 8 or 9 am: Cake for breakfast again.
Thursday Morning Cake for Breakfast again. This is about the MAX time frame a cake will last us. Just slightly above 48 hours or so.
Sometimes I or she will have 2 slices each day or sometimes we will cut different sizes which effectively SHORTENS the timeline above. Of course the opposite can be true as well and we can lengthen the time the cake lasts if we want. Cakes also have totally differing caloric amounts as all cakes are not created equal.
So I hope this helps you in seeing how a Cake lasts us 2 or so days. (Somehow I don`t think it will help as you probably won`t understand. Let me know if additional help is needed)