@twentydxllars
Ah, sorry for the confusion I know I explained that kinda bad. You have it exactly right though in your example! The italics are mainly just to show the separation between present thoughts and a memory/conversation/flashback
So standard text would be: Marjorie writing in her diary right now (her present thoughts).
And text that is italicized: The actual memory/conversation/flashback she is referring to.
I’ll give you two examples
Example 1:
The instructions were simple: Make a how to video; must be in groups of four; due on Thursday.
[This should be easy.]
Now that school was over though, Monty was seriously regretting it.
The character’s thought is italicized to separate it from the rest of the text. This is how I mainly show what a character is thinking in the moment. This is more suitable for dialogue heavy chapters.
Example 2:
Her foot steps closer and Monty's steps back, thanking her awkwardly.
["Rachel, you're a cool girl and all but I don't like you like that. Plus, I have feelings for someone else that I need to deal with."
"Of course you do."] Two pairs of shoes then become one when she walks away.
In this scene, a video is being shown to the class and this conversation happened off screen. So to show that it’s not happening in the present, it’s italicized. Notice how I didn’t italicize the rest of it? Your example actually makes more sense since you’re writing in diary format (aka first person).