I don't really have an answer for you but after reading your post, I just wanted to send you love and let you know that I think it's more than likely a case of you being a wonderful mum, just going through a hard time. I don't believe that you are a terrible mum and that your kids would be better off somewhere else. I hear what you're saying - that you get angry so easily but you also say it's because you're unhappy and you also tell us that you're in therapy so right there it tells me you're a great mum. You're aware of what you're doing. You're aware of what needs to change and what you want to change. You're taking action to change these things and to help you through this difficult period. You're worried about your kids and want the best for them. You are the best for them. And you will get through this. Big hugs to you for doing everything you can for yourself and your much-loved children.
(PS: you say they have a "full on after school schedule". Is this necessary? Is this perhaps something that is just adding more stress to your life right now? If it's all things they love doing and you're happy with them doing it all then that's fine but it's also ok to not have anything scheduled for after school and just come home and play. Get them to earn their screen time by doing jobs around the house. Give them ownership of when they are on screens. Eg: you tell them they have x amount of hours on screens during the week and it's up to them when they use it. So if they use it all up in the first couple of days of the week then tough, they have no more time. They will soon learn to distribute the time across the week if they don't want to run out. I'm not saying this is a fool-proof plan and I don't know the ages of your children, but it's something that works well for my 10 and 8 year old. They know how much time they have each week to use and then they decide on which days they're going to use it and they're surprisingly very responsible with it and deny themselves time on the computer for a day when they want to save it for another day when they plan on playing online with a friend for example.)
Anyway, sorry for the long post and wishing you the best of luck. I'll be thinking of you.

You will get thru this. You are doing everything right and helping yourself.
Your kids are lucky to have you as their mum, you obviously love them so much.
Chin up xx

I've worked with kids, who have mothers who are abusive and have problems, and the kids have been removed from their care. But they always want mum. Even if mum said I'd rather kill myself than see you again. Even if they end up living with the best grandparents or foster carers or someone who loves them like their own. It's never the same. Kids always want mum! ♥
You're on the right path to seek help. Good luck

So many good answers here that I don’t think I can add much more to; apart from I just want to say you do care about them and love them and they deserve YOU so don’t ever think They would be better elsewhere as no one can ever love them like their mum❤️
Also, so many of us feel like this. And the things you say aren’t emotionally abusive hun. Be a bit kinder to yourself and take time out for yourself. You are doing an amazing job I take my hat off to you being a single mum 💕💕

You did not say how many kids you have and what ages they are. If they are old enough you could give them duties, in return for pocket money. That will reduce the pressure on you to do everything.
They are a lot more capable than we give them credit for.
Yes, you will sound like an army drill sergeant as you monitor their completion of jobs, until they learn its easier to do the job than put up with the grilling they get when they dont, but it is part of educating them to be responsible adults.
There are also some jobs that they should do without payment, as part of being a family.
There are some good books around that might help. Google "raising reponsible or resilient kids", and see what comes up. Many of them are available in BigW, or from libraries.
Lots of good articles might come up too with that type of search.
You cannot be expected to know all the answers to raising kids yourself.
It used to be said that "it takes a village to raise a child". But often Mums are left to do it all themselves these days.

Do go to the doctor if therapy is not helping. You may need something else as well.
Ask for total bloods to be done, so a specialist can tell if anything that looks approximately normal, but is on the low side, could be the source of the problem.
You may be low on iron, so constantly tired and feeling like everything is on top of you. That is very common for women.
Another which is a scourge of many women is low thyroid.
Not low enough for a doctor to say its anything to worry about, but specialists in that area would immediately know you are "under par".
With the presure of life you may not be getting enough good nutrition. Over time that can have you getting low on the vitamins you need.

When you recounted what you say constantly to the kids, it rung bells for me ! In fact I think you may have a secret recording of me from years ago.

Thats what most of us sound like. Kids are just plain exhausting these days. They challenge, they get distracted - especially by devices. They never get ready on time. They leave their things all over the place and can never find them. Its part of being a kid, and the stresses are part of modern life.
A big issue is that so many Mums think their kids lives should be full - including after school activities. You just run and run. No wonder you feel stressed.
You probably need some time to yourself, time to just relax. Time to soak in a bubble bath, read a book, just sit and watch the world go by, birds in the trees and on the power lines squabbling over sitting locations. Just plain time out.
Have you got anyone who could take them for a couple of days so you could get some "me time".

Don't ever think they would be better off with someone else. They wouldn't. You love them, you care about them.

Those examples you have of what you say to your kids are far from emotionally abusive.
Are you sure you're not just being too hard on yourself honey? We all go through rough stages in our lives.