My situation was a little different, but I figure if I can do it...
I was 21, with a 2 (3?) year old, working 30+ hours a week, and going through a 2 year college program (related to my job). After the first year, my then-husband left, so I became a single mom on top of that.
I wish I had dropped to "survival mode" and not tried to super-excel at school (I couldn't help it, I had always been very driven, had to be top of the class, etc). My "tips" for survival (although some is fuzzy because that was 18 years ago...)
Set up as much as you can to just be routine. The less you have to think about the day-to-day stuff, the better.
Clothing-- wear stuff you can wash in one or two loads. You don't want to be stuck doing loads of laundry, so minimize the wardrobe. Who cares, no one will really notice, and if they do, invite them to do the laundry for you. (for me, this became especially important when my washing machine died and I was stuck doing laundry in the bathtub for about 5 months. I couldn't afford a laundromat or to replace my machine.)
Food-- batch cook if you can. Make a large meal and freeze half for later, eat the rest as leftovers. Make simple, easy, fast, but good food. Spend a few minutes and cut up a bunch of oranges (or carrots, or celery, etc). There were days where I was just too tired to build up the energy to peel an orange, but if they were already cut, all I had to do was eat.
Commute-- take advantage of this time to do whatever you can to make the rest of life easier. I wish smart phones had been around back when I was doing this! Pay bills, do a little studying, whatever. Maybe even nap sometimes.
There are going to be some rough days, but just power through them and remind yourself that there is an end to it where you can get your life back. I had a solid goal--for me, the job was tied to the schooling. If I didn't do the school, I didn't get to keep the job. The school would lead to an apprenticeship program, which would lead to a great career. I was going to need that career if I was going to make a good life for my son and I. So, figure out your goal, and do what you need to do to succeed.
Good luck!