Marital financial stress

Okay ladies. I’m married. But recently we hit a rough patch. Financially. Money is very tight. We have 3 kids. We both work and it’s enough to pay the bills and put food on the table for the kids. But we have one car (that is my car since high school.. his motor blew) . So the one car situation is tough. But besides that, we both just financially frustrated. We don’t have enough to buy another car. We sacrifice a lot to buy clothes for the kids and food to eat and to pay bills so we don’t have the luxury of doing things. But because of it, we just argue like what bills are most important to pay or just financial stuff period. Parentally we are satisfied that our kids have clothes and food to eat. But it’s frustrating when you wanna have lunch at work but can’t pay for it so you eat a sandwich you made from home or left overs. Sometime no lunch because you gotta have lunch $ for the kids. We can’t apply for food stamps. Apparently we make too much 🤷🏽‍♀️ I don’t see how. It’s just enough to pay the bills and I’m smart to buy food from couponing. I really wanna back to college and finish school to provide more to the family. Just hard to live when you live off minimum wage. So my question is......How do you make it work in a marriage through a hard time of financial struggle? We both just tired of struggling. Tips??