Hi everyone.
Thanks for all of your messages of support as always! 
I'm sorry I haven't been on here this week, to be honest everything has been really draining and I've kind of shut down! Loads has happened since my last update, I'll try to set out a summary...
So, we agreed to sit down and discuss arrangements for our daughter on Tuesday evening. I had wanted to do it all via a mediator, but he pushed back on that (given the cost) and said we may as well try and discuss ourselves and then if it doesn't get anywhere then try the mediator.
I proposed 5 nights a fortnight with him, including a full weekend every other weekend (fri night - mon morning) plus two midnights during the working week on the other week. He absolutely ruled that out and suggested something that gave him 6 midnights, but I wasn't happy with his proposal as he basically had her switching between us every two days - clearly not a good pattern for her which he refused to reconsider!
Obviously the conversation escalated and he started saying things like he'd take me straight to court for at least 50% and he may go for full custody as he's better able to look after her than me (
) because he's emotionally stable and earns more ( again). He also got nasty and said that if it goes to court, he'll make sure he includes that she can't go to my parents because their dog attacks her (absolutely untrue), and he won't be flexible around Mother's Day/birthdays etc. Ended up with quite a lot of extreme verbal abuse. He also started saying stuff about me being really ugly without make up and laughing at how I looked, and other unkind personal things like that 
I tried a few times to sneakily record him, and I did succeed actually. However he became suspicious of it which wasn't helpful!
The following morning he came down and said something rude to me which I ignored. I was just in the middle of emailing my solicitor so quickly shut off my phone, and he decided that I'd been writing notes on him. He got really aggressive, tried to wrestle my phone off me, and basically said that once he'd dropped our daughter at nursery he'd getting my phone and I'd show him what I'd been doing. When he arrived back, he'd obviously realised he needed to play it cool as I may be recording (which I was). He started talking really reasonably about how he was trying to be civil and all he wanted to do was agree things nicely with me, yet I kept trying to trap him and record him when he was doing nothing wrong. While he was saying this, he was writing really unpleasant messages on his phone and showing them to me to read (ie so nothing would be recorded).
One of the messages he showed me to read silently said 'watch out on the stairs, they can be slippy' - that made me cry, and he was like 'why are you crying, I'm just stood in the doorway, why are you pretending i'm doing something wrong.' and so on!
The next day he emailed an updated proposal for our daughter which I'm much happier with. It gives him 6 nights a fortnight but it's a better pattern for her and I think it makes sense. So I'm inclined to agree to it.
I also spoke to my solicitor just before he emailed that through and she didn't say anything that gave me any reassurance that he wouldn't easily get at least 6 nights if it went to court, and she said that it seemed like it could be a reasonable proposal if it worked for our daughter and if we build up to it slowly. In terms of his behaviour, she said that it's not uncommon for things to escalate between couples when child arrangements are being discussed, as it's highly emotive, and so it's unlikely that his behaviour would make any different to any agreements if it did go to court, providing it wasn't impacting our daughter. She said that I could either log it with 101, or keep a detailed diary. So I've decided that if anything happens again I will call 101, but in the meantime am writing everything down.
He apologised on Wednesday night for being 'mean' and said that he was sad, and was easier for him to be angry than sad so that's why he'd been behaving like that. Since then he's been really friendly and charming (asking for snugs!! Wtf). I don't really care though as long as he's not in a bully mood!!
In terms of what's happening next, he's away for the weekend (yay!) and we have agreed to discuss child arrangements on Sunday night again. My aim will be for us to plan to come up with an arrangement that ultimately ends with his proposal, but builds up gradually to give her time to adjust. Once that is done we can discuss financials again- but my starting point is 50%, and I won't discuss anything else without a mediator present.
Finally, I'm going to spend the next few days cleaning and tidying so the house looks good for when I get someone to come and value it 
Sorry for the brain dump, and I hope my update doesn't alarm anyone. I have support, and I am leaving some clothes of mine and my daughter's at a friend's house so that if he does turn sour again we can easily go and stay elsewhere.