Okay, you're going to have to petition for divorce. There are a number of options on which to petition:-
1. Her unreasonable behaviour, you would have to list examples of such behaviour and explain that if you are still living in the same property then you are effectively living separate lives and do not have a shared domestic home life.
2. Two year separation with your wife consenting to this
3. Five year separation without her consent. (in this and 2 above you would have to prove that if you are living in the same property then you are effectively living separate lives
4. Adultery, if she has committed adultery during the marriage then you can petition her based on this if she is willing to admit to and you have not co-habited for a period (or periods together) of 6 months since the adultery. You can still petition on this ground if she does not admit to it but it would be a defended case and you would be required to prove the adultery. Very few divorces are defence in this way because it is very time-consuming and very expensive.
There is information on divorce and the divorce process here:-
In view of the fact that you have assets I would strongly urge you to instruct a solicitor to act on your behalf because she will seek a financial settlement. You can find solicitors who practise in your area here (select "family law" and enter your postcode:-
It's a very difficult situation, I do sympathise.
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