Good morning. I'm not 100% clear why you are pursuing this in the county court rather than as part of the matrimonial proceedings. However, you have taken that decision and I'll do my best to assist.
There's one point that your husband hasn't raised, and this is limitation. This concerns me.
Effectively you are suing under breach of contract. Assuming there was no formal deed executed for the loan, the limitation period for breach of contract is 6 years. On the basis of the facts pleaded in your form, the breach occurred in August 2014 when he stopped paying. So you would have had to issue the claim by August 2020 to be within the limitation period for a claim.
He would have a complete defence to the claim if you are outside of the limitation act period for bringing the claim. The judge would have a duty to bring this to his attention should this get to court without settling, and you could then be liable for costs if you have fallen foul of this.
This aside, whether this is decided in the county court or the family court, the case will turn on evidence. You, as the claimant have to prove your case. So you will need to show that the loan had not been repaid as per his argument that it has and you need to demonstrate how and why it has not been repaid.
You also need to be clear that you lent it to him in a professional capacity not a personal capacity. In general loans between spouses are not actionable as spousal property is all considered jointly owned (hence the phrase in wedding vows - "what's mine is yours").
So, the matter will simply be decided on the basis of evidence presented to court. The party that presents the best case is going to win the argument.
I hope that this assists? Can I clarify anything further for you?