I think your spouse has made it very clear she wants a divorce so you need to do the following things
Decide what you want in the future as a parent. Do you want to have your children live with you and take a full 50% parenting responsibility? If so your needs will be housing for you and your spouse that is suitable for your children to live in. This may be the costliest part of the divorce so give it plenty of thought.
Keep a record of all your current expenditure with receipts so that you can show how much of your income you are investing in the family.
Start saving for the divorce, assume €10k minimum.
Hire a solicitor and get advice.
Get counselling for yourself. You need to let a lot of the negativity towards your wife go.
Each party will come out of the divorce poorer and in a poorer financial position, so you need to be realistic on what you will need your money for in the future.
Continue to be a parent to your children now while this is all playing out. Do you screen the second level students from the turmoil enough?