You are doing fantastically well.
Anyone would display symptoms of disorders like you have said when they are subject to abuse and control all day every day. It's torture. There is nothing wrong with you, you are reacting perfectly normally.
Now you are going to have to be very vigilant and observant. The parts of our brains that detect threat and safety are very primitive, and they get easily confused. Over the next few days, you'll very likely find that your memories of the abusive incident and previous abuse start to fade or fragment, because they don't fit in to the narrative of him being your loving husband (which your "primitive" threat-detecting brain likes a lot, because it feels safe and makes sense). The wish for everything to just go back to normal can be extremely powerful, so much so that it can actually override your real memories. The modern/evolved bit of your brain that can do reasoning and understand that one person can act in different ways is not as well equipped to detect threat, so it won't be as good at overriding the "Danger! Seek safety!" signals, instead it tries to make sense of them, so you will find that thoughts creep in like "Well it was out of character" "Now he's done that, surely he won't do it again?" "He was REALLY stressed/grieving/drunk, maybe it is excusable" "I was being really difficult".
This generally happens to perfectly coincide with the abusive man's apparent 180, when he realises that he really might lose control of you and turns on the charm - he will be apparently remorseful, he will cite how much he loves you, he will claim to be heartbroken/desperate/suicidal, you will have ruined his life, taken his children, ruined his career (whatever makes you feel guilty). He is likely to come up with all kinds of promises, often extremely vague when you actually look at them (I'll do better, I'll treat you better, I'll go to counselling, I'll get help, we'll be a real family, give me one more chance, I promise I will never). Sometimes they do start doing specific things you've always asked for, like buying flowers or making dinner or looking after the DC.
Notice that the apologies are generally about him and what he has lost. Not about you and how you must have felt. Notice that the promises are grand and sweeping but lack specifics. They say they will go to counselling, but they expect you to arrange this and then they probably won't go/engage. (Regardless of whether you want to try again, never go to counselling with an abusive partner). Notice that they seem to have known/been listening when you tell them what you wanted from the relationship, but they only bother to do it now, when they think they are about to lose everything. They don't do it day to day when you wanted them to do it.
The combination of that glimpse of how you always wanted the relationship to be, the wish that everything could go back to normal like before this ever happened and the knowledge that you could make it go "back to normal" by forgiving the incident is really hard to fight - it's exactly why most people go back to abusive relationships multiple times, even when from the outside it looks really obviously like a bad idea. But you must fight it (and you can!) because it is never ever true, it is false hope, abuse always repeats and escalates.
This is what you can do:
- Keep your memories of the abusive incident clear. Write down what happened, what you felt and thought. Take photographs of any physical damage (e.g. the wet patch on the bed), bruising, etc.
- Write down any other things that you can think of - your "boiled frog" comment. Whether this is in a private diary, in discussion with a counsellor (there are charities which provide DV specific counselling) or on something like a MN relationships support thread.
- Read/learn everything you can about abuse dynamics. Lundy Bancroft Why Does He Do That is excellent or the book Living With The Dominator, or the Freedom Programme.
- Tell everyone you know IRL. Reporting to the police is EXCELLENT. When other people know about it, it becomes more real and is less easy to just forget that it happened and return to normal. Getting authorities involved is even better because you will have for example social services not wanting your children to be in this environment, which helps remind you that it is really serious and not just something to ignore or excuse.
- Don't engage with him. Absolutely minimal contact. Screen it through somebody else if you have the option. Choose someone who will be hard as nails unsympathetic. If he does the threatening suicide thing, ask the other person to contact the police but not tell you.
- Do engage with any agencies/authorities put into place to protect you and the DC. Contact Women's Aid and/or your local police DV unit, take everything offered.
- When you feel able, no rush on this at all, start making changes and doing things in your home that he would have objected to or made a fuss about to make it your own. Revel in watching what you want on the TV, squeezing the toothpaste the way you like, listening to music. Sing along if you want to. Get your hair cut. Rearrange the furniture. Buy new bedding. Throw out the picture you always hated. Whatever makes it feel like you are in control in your house.
- Reach out to family and friends. Abusive men often corrode their partners' support networks by damaging relationships. Sometimes the damage is done, but some people will be delighted to hear from you and keen to meet up. Invite them over, spend time nurturing and strengthening those relationships. Notice what it feels like to spend time with people who actually like and value you. Go out to groups in your community - toddler groups or summer holiday meet up things. Make and strengthen all those connections.
Good luck. You can absolutely do this. MN is brilliant for keeping you strong.