hallo, I am a mumsy older woman, offering a hug and cup of tea. I sympathise massively with how your life is right now. If it;s any consolation I felt exactly the same even with DH around so you are coping better than me.
Two things massively helped me when I felt like you did. The first was a set of books called Positive Parenting. I just read them cover to cover a few times and it cured my shouting. I just reacted in a completely different way to DC and we all calmed down. It is a bit time consuming but if you are currently not working that's an ideal time.
The other one was the 5-minute fix. If you have really bad ADHD, you can make it the 2-minute fix.
Get a bin bag and a box or laundry basket
Pick a room.
Set an alarm for 5 mins on your phone. In that 5 mins do as much as you can to make the room look tidy. E.g. bathroom - chuck out dusty old bottles of stuff you don't use and empty loo rolls. Hang up towels, wipe mirrors and taps, line up bath toys neatly.
When the timer bleeps you're done.
If it's the kitchen - empty the bin, wipe the surfaces down and soak any dirty washing up in very hot soapy water.
You can do the same with self care. Set timer for 5 minutes - clean your teeth, cleanse your face, comb your hair. You feel instantly more alive. Or have a 3-minute shower. Get wet, soap all the bits that sweat, rinse off. You are out of the shower before the timer goes.
The 5-minute fix proves to you what you can do in a tiny amount of time.
You can 5-minute fix dinner - even if it's microwaved beans and wholemeal toast with chopped banana for pudding, it's healthy. Or filled pastas with a jar of tomato sauce and some sliced cucumber and carrot on the side.
And don't feel bad for not working btw, you are raising two small children. That's a job. Just do this job for now until the littlest one is at school. It really helps to have a plan and make a decision about it. For now, so long as your benefits are secure, your job is to raise your kids, sort out your home and yourself, in prep for starting work when your youngest goes to school. You can make a little list of stuff to do towards this, like looking at access courses or getting your youngest assessed for SEN.
CAB might help with the debt. Whatever you do, try to let who you owe know that you can't pay it all right now, so it doesn't escalate.Try to get a payment plan that you can afford. Dont't take out a payday loan.