From your question I see that your issue is with the property regime in Ireland. I can perfectly understand your confusion, because although they name it the same ['separation of property'] attorneys from the Continent and from Ireland refer to two different systems. As an attorney with both civil law and common law training, please find my explanation:
1. During the marriage, the matrimonial property regime in Ireland can be called 'separation', as in Andorra, because during the marriage there is no common property and each spouse owns their own property. However,
2. at the end of the marriage, the Irish matrimonial property regime becomes a sui generis (not named) one.
Specifically, even though each spouse remains the owner of her/his property, the Court, at its own discretion, and looking only to precedent and not to some written rules, may award (i.e. give) one spouse some of the property of the other spouse.
The general reasons for doing so are:
(a) the income, earning capacity, property and other financial resources which each of the spouses concerned has or is likely to have in the foreseeable future,
(b) the financial needs, obligations and responsibilities which each of the spouses has or is likely to have in the foreseeable future (whether in the case of the remarriage of the spouse or otherwise),
(c) the standard of living enjoyed by the family concerned before the proceedings were instituted or before the spouses commenced to live apart from one another, as the case may be,
(d) the age of each of the spouses, the duration of their marriage and the length of time during which the spouses lived with one another,
(e) any physical or mental disability of either of the spouses,
(f) the contributions which each of the spouses has made or is likely in the foreseeable future to make to the welfare of the family, including any contribution made by each of them to the income, earning capacity, property and financial resources of the other spouse and any contribution made by either of them by looking after the home or caring for the family,
(g) the effect on the earning capacity of each of the spouses of the marital responsibilities assumed by each during the period when they lived with one another and, in particular, the degree to which the future earning capacity of a spouse is impaired by reason of that spouse having relinquished or foregone the opportunity of remunerative activity in order to look after the home or care for the family,
(h) any income or benefits to which either of the spouses is entitled by or under statute,
(i) the conduct of each of the spouses, if that conduct is such that in the opinion of the court it would in all the circumstances of the case be unjust to disregard it,
(j) the accommodation needs of either of the spouses,
(k) the value to each of the spouses of any benefit (for example, a benefit under a pension scheme) which by reason of the decree of divorce concerned, that spouse will forfeit the opportunity or possibility of acquiring,
(l) the rights of any person other than the spouses but including a person to whom either spouse is remarried.
The relevant legislation can be found here: http://www.irishstatutebook.ie/eli/1996/act/33/section/20/enacted/en/html#sec20
As you can see, this is very broad indeed, and in practice it depends on the arguments of each spouse / attorney to move the Court's decision. What I should also mention is that, if there is a matrimonial contract, the Court should endeavor to respect it as well.
I hope my answer was useful and look forward to your rating.
Dr I L Vlad