There is no automatic financial clean break between a divorcing couple.
If you wish to have certainty regarding your financial situation then a court order in relation to your finances needs to be obtained. This can be done by consent or if necessary by making an application to court.
If you do not have a court order then even after divorce either party could make applications to the court to make claims against income, capital and pensions at any point in the future.
Please see the recent high profile case of Dale Vince whose ex-wife made an application for a lump sum and spousal maintenance 30 years after they separated.