After you cease using the house it will not attract CGT for 12 months (to give you time to sell). Your wife moved out in Oct 08, so it only becomes liable for CGT this month. Say you sell in 3 months time - CGT will be calculated as 3 months gain over the 10 year period
For example, you make a profit of 200,000, and owned the house for 10 years, your CGT would be payable on 1/40th of the profit, or €5,000. The tax rate is 23%, so you'd pay approx 1,200 in tax.