He is an abuser. It's not "verbal and emotional abuse", it's been domestic abuse. Coercive control. Abuse is about using power and control to break and dominate someone. The specific tactics used (e.g. Verbal nastiness) are secondary. When you get sucked in to labelling specific tactics you miss the bigger picture and don't see that the whole thing is a cycle of abuse.
The whole relationship was abusive, not just the Times he was saying nasty things. The 'good' times were part of the abuse - part of keeping control of you and how he trauma bonded you.
This is the best thing for your children's wellbeing. Look at developmental trauma. This protects them from lifelong damage and suffering that spending a childhood in an abusive home causes.
As to how you get through it...
One thing at a time. Focus on the present not all your worries and emotions and what ifs.
Emotions are temporary, they never last forever. Strong emotions come in waves, so care for yourself. Be kind and compassionate as this soothes your central nervous system.
Do one thing every day for no reason other than because it makes you feel good.
Make a list of things you need to tackle. Prioritise them. (Urgent, must be done, nice to do, one day - dates for anything time critical). There are apps you can use to help.
Do the Freedom Programme course. Inform yourself about why it is critical for the health and brain development of your children never to resume this relationship. Understand the cycle of Abuse for yourself so that you can recover.
Get support. Real people, online people, professional people. Therapy, support lines from DV orgs, Samaritans (they're for anyone in distress, not just suicidal).
Trauma therapy. You will need to explain you have experienced "domestic abuse" - using those words - so you receive the correct referral. Counselling is not safe for someone with trauma (NICE guidelines say as such it you would like to confirm for yourself) as it makes things worse so you have to tell them you're traumatised to make sure you are assessed and referred to the correct therapy.
Distract yourself. Dwelling and ruminating makes you feel worse. Do activities with other, build your social network so you are not isolated, have activities to do at home (even if it's just puzzles or colouring or music).
Use apps like Breathe or Calm to help you learn breathing techniques and other strategies.
Give yourself goals, however small ("this week I want to clear one item from my to do list" or "cook my favourite meal"). Start a notebook and each night write down everything you achieved that day, however small. On tough days, eating a healthy meal or showering are both achievements to give yourself credit for.
Journal. Write down worries to get them out of your head. Write down successes to remember them. Doodle. Confide your feelings in the page.
Ask for help when you need it. Accept help.
Use the words "domestic abuse" when asking for help from services and professionals so that they understand what's happening and can give correct advice. If you don't do this or just name tactics like you did here, then people will misunderstand you and give bad advice. It is important.
Money Advice Service website has lots of good advice on financial matters and budgeting. When things feel overwhelming it can be useful. Money saving expert can be good too.
Citizens Advice website is also a wealth of information on navigating bureaucracy and legal matters. Make use of resources like that. Knowledge is power.
The more you do like this to take control of your life, the better you will feel. Feeling in control of our lives is a really important human need that abuse takes away and creates a feeling of helplessness. Feeling helpless makes you feel hopeless and distressed. Acting helpless stops you making life better.
You are not helpless, but you do have to start acting to prove that to yourself and re-learn how to live a healthy life free from his abuse.
Take control of your life back. It is a very, very positive thing that you and your children now have the opportunity to build a future safe from abuse, even if it doesn't feel positive yet - seize it with both hands.
You can do this.