Oh no :( I'm so sorry to hear your update.
However, there are a couple of things in it that not only highlight how he was only paying lip service to change in the first place, they show him as actually controlling and abusive.
He thinks so little of your needs that he utterly disregards what you have agreed and comes round because he fancies it, despite knowing that you didn't want him to. He thinks you are way less important than him and your feelings are not valid.
When you're sitting downstairs crying, he makes no attempt to console you, and instead walks off and leaves you.
He's talking about you behind your back. And I bet he's doing it to his friend who dislikes you, and most other people you know as well.
The one with the waking your DD up to brush her teeth is the worst in my eyes. It's not only horrendously, deliberately undermining (he knows you've done it, he's trying to make you doubt yourself) it's cruel to your DD, waking her up to brush her teeth when she will know that she's done them. It will confuse her and mess with her reality and that is abuse of her. Frankly, if my DD had eaten 3 creme eggs and then I'd put her to bed and I actually had forgotten to brush her teeth wouldn't let DH wake her up to do it, one time won't hurt! (DD doesn't do this BTW as she's only 9mos and hasn't even heard of creme eggs yet before I'm accused of being a bad mother!)
When things didn't go his way he ran away again.
You mention that you're younger than him and I wonder if that is something that comes up a lot in your relationship, he's assumed the "older wiser" mantle and uses it as another way to look down on you. Age difference should not mean that he automatically is right and you are young and naive and wrong. My DH is 7 years older than me and if he tried to look down on me because of my age I'd laugh at him. We're equals, otherwise what's the point?
It looks like FIL has downgraded his status from "spineless wimp" to "lying manipulative git" as well. At least you know not to engage with him at all any more.
You seem resigned to MIL and FIL coming round to your house this week, and I don't understand why. They don't have any rights at all of access to your DD. You have no obligation to let them into your house. Your H doesn't have keys either, so he can't let them in. If you let your H take DD for the day (not yet, I can't stress enough that you should only allow supervised access for now) then he might take her there then you can't control that, but for now, they have no rights. If they turn up, don't answer the door. If they tell you they are coming round at a certain time then be out. They have no rights. Your H is living away at the moment, he doesn't have the right to invite other people to YOUR home.
I can't say to you enough that what is happening to you is not normal. It is not normal human interaction, it is interaction between a normal person (you) and three people who wouldn't know normal or sane if it crammed a banana down their hole (thank you BBTB for that wonderful image).
Did you keep up that solicitor appointment for the 1/2 hour call? If not, pick that up again, ring around some other solicitors, get back on to the CAB and start making plans as if you are seperated. Ask him not to contact you for a few days and in that period of no contact (use that period to get all your ducks in a row and know where you stand, don't tell him that's what you're doing) then talk to him calmly about access and so on. This doesn't mean you can't go to relate, but do it from a position of strength.
Keep repeating to yourself:
I am normal
My feelings are as valid as anyone elses
I am reasonable and calm.
Because all those thing are true, it's the people around you who are insane