If the marriage/relationship is less than 7 years and there are no children of the marriage it could be considered a short marriage. The rule of thumb is that you take out what you put in and split the increase in any property values 50:50. The same applies to marital debt.
Pensions would not normally be a factor in a short marriage. If there is to be any offset against equity, it would not be on a £ for £ basis. A considerable discount would be applied because £1 of pensionat some point in the future is not the same as £1 cash now.
The reasons for the divorce have no bearing on the finances. To remain in the property you would need to be able to take on any mortgage in your sole name.
So there is £80k of \"personal debts\" broadly split equally.
£40k house equity but £13k of debt so £27k of equity and an £18k pension.
How much has she suggested she wants of the house equity as given there is so little you look to be arguing over almost single figure £1000s. i.e. you take £14k vs her £13k or maybe £15 vs 12 if the pension is coming into play at all