Family court, advice needed

[Ginger26]

I'm currently waiting to going through family court proceedings for a child arrangements order.
I am the respondent and am representing myself.
I have been filling out the paper work which all seems to be me having to reply to all the lies my ex has came up with, accusing me of coercive control amongst other things.
I have just found several things I posted on a forum when he became abusive towards me and it is literally like a diary entry of everything that went on at the time (obviously details do get forgotten but this has everything)
Can this be used as evidence that its actually him that's the abuser?

Yes any contemporaneous note of things that happened can be used as supporting evidence, so you could reference having made a note at the time and include screenshot as an exhibit. I used to send regular whatsapps to myself detailing what had happened each day for months, so that it was dated/timed, and used some of these as exhibits to support particular events occurring.

Trawl through and see if you have any messages from him that would concur with it too.

I do have some messages but I know I have loads on an old phone, I just can't find it. He's been a lot more careful in the way he texts since being with his new girlfriend, I do think she writes a lot of the messages for him because are not worded the way he would.
Did you manage to prove the abuse?
The amount of points hes raised I need to respond to is so lengthy and with a baby I'm really struggling to find the time.

Just ensure you also evidence that the forum post was actually you. Otherwise in theory everyone could just trawl the internet and claim a post was theirs. Can you still login to the account or do you have emails from the site confirming your username?

Yes I can still login and I retrieved about 10 screenshots documenting abuse over when my daughter was born and continuing a year later. The post from when my daughter was born actually align with a police report that he's not aware of as I didn't want him speaking to but wanted it documented.
The police report matches my post from that time but with more detail

The focus in family courts will be less on what happened and more on how you’ll work together to promote contact. (Which I know is shit.)

Make sure you file your own C1A form to set out his abuse of you, rather than just responding to his allegations against you. The Court will then decide whether further evidence is needed to consider the allegations, and if so will order statements to be filed. At that point you can attach copies of texts etc as exhibits to your statement.