If he doesn't back down then you will need to issue financial remedy proceedings to determine the issues for the house and any other assets (including who lives there, etc). As the primary carer you will likely be allowed to stay in the property certainly until your Daughter is 18.
Assuming mediation fails or your husband doesn't agree to mediation then you will need to issue financial remedy proceedings and you would need to complete and send two completed copies of Form A (one copy is attached) to your local family court and pay a fee of £255 payable to HMCTS. If you are on a low income or have low savings you can ask the court for help with the fee here https://www.gov.uk/get-help-with-court-fees
The court will then list a first appointment and give directions for a financial dispute resolution hearing (FDR) where the judge will give their opinion on a likely settlement - which usually prompts a settlement at this stage. The court will ensure the parties make full and frank disclosure of their assets and liabilities to ensure the financial positions of you both are known and to allow the court to make a settlement decision. If the case does not settle, further directions will be given and a final hearing may take place if neither of you can agree to settlement terms.
To apply for a judicial separation, the site is here: https://www.gov.uk/legal-separation
To apply for a divorce, the site is here: https://www.gov.uk/divorce
And for information on a financial order: https://www.gov.uk/money-property-when-relationship-ends/apply-for-a-financial-order
Finally, if you need money before the divorce finalises you can apply for “maintenance pending suit”, which means you ask the court for an order that your ex pays you support to help with bills and so on before the case finishes. You will need an application form under Part 18 of the Family Procedure Rules 2010 and the fee is £155. You would need to attend a hearing for this.
You can apply for a financial order once the court pronounces decree nisi. The mediator will also have to sign off the Form A to say you have attempted it and you can then issue the financial claim.
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