The best gift you can give your children is to take care of their mother. Have you ever listened to the flight attendant safety speech? "Put the oxygen mask on yourself before taking care of those around you." So you need a break. And you need to make it happen, not just pine away for it when everyone else has their needs meant. That will never occur!
Why does your husband's exhaustion matter, and not yours? Why are you in charge of all the household tasks plus child care plus college? Your husband works, what? 40 hours? 50? 60? And you work about 120, if you're the average homemaker. So there's something wrong with the math.
Beyond that, you are - for heartfelt reasons - teaching your children that a woman's job is to get sick and wait on everyone. This is the lesson for your 10 year old daughter - "You, too, can aspire to be exhausted with no life and no friends." And your lesson to your sons is, "Here's how to treat a woman, boys."
None of you wants this. Here's what you have to get through your head. You are not a bad mom if you are also a person. You are not a bad wife if you are also a person. The kids need to be responsible for some of their own stuff - picking up their own clothes and getting them to the laundry, putting away what's folded, matching their own socks, etc. They can wipe down the bathroom counter and put everything but glass into the dishwasher. They can sort their own snacks, and clean out their own backpacks at the end of the school day. They can do the recycling and the trash. They can, and should, do their own homework. It's not your job to be sure they get As. It's their job to do what's assigned and stay in for recess or explain it to the teacher if they fail to do so. They need chore charts and checklists, not you verbally staying on them every second. This is how they learn life skills and independence.
You need to plan at least 2 days to yourself per month. That's what I did - I dropped my kid at preschool and took off for the day. My husband picked him up, gave him lunch, put him in for a nap, dealt with him when he got up. You can do this on weekends if your husband can't get the time off.
You also need to cut out at least 2 "must do" tasks that your family will survive without. Scale back your standards of what constitutes a "good job" and let something slide. Not every bed has to be made every day, you know?
You must go to the gym, or join a volunteer group, or something where you can meet your own needs for being restored and also meet some friends. Find someone who wants to go to a midday movie with you, or try the new Thai place, or go to a wine tasting, or check out the new exhibit at the art or science museum. Get free/discount passes at the area libraries.
Do not wait until everyone else says it's okay for you to be a full human. Make it happen. If you can't do this alone, get counseling or find a life coach short term to get your life on track.
Yes, you signed up to have kids. You did not sign up to be a slave. This was your choice - and you aren't stuck with it forever. I've returned outfits that don't fit, and I've bought a new model car when the old one wasn't right. Same for you and your lifestyle.
Good luck!