Triggered by other people’s food choices

I have two stepsons living with us, and I’m very triggered by their food choices. They have no manners when it comes to food. They take far more than their share, regardless of how many people are eating. They hide food in their room even though that’s against the family rules. They steal and eat others’ food. It’s maddening, but I think I’m so triggered by it because of my own issues about food and fear of missing out. I’m also bothered because their mom hasn’t taught them any manners.

How do I handle this so I’m not triggered constantly? I know their choices are their own, but when it affects other people and the family budget, it’s irritating.