Hi Simon
Sorry to hear of the position you are in, and I can understand what talking to a complete stranger can offer, At they will not know either party involved and therefore there wont be any side taking.
Obviously, the humourous posts here like "punch her in the ovaries like previously mentioned are light hearted and intended to make you smile, but they dont offer a realistic way forward.
My best mate split with his wife a few months ago after 2-years of marriage so I know what your likely to be experiencing, he is my best mate, and his wife is my wifes best mate, so we were stuck well and truly in the middle.
You didn't mention it in your opening post, so can only assume that there aren't children involved, in which case thats a positive thing.
My suggestion would be for you to move out for a few weeks. I know this can be seen as running away from the situation, but this will allow both you and your wife space, and allow you to both think clearly without getting into arguements and making the situation worse. I assume you have family or a friend nearby that can put you up for a short while given the circumstances.
Dont make any contact with her, but before you leave advise her you will stay away for a while, 1 maybe 2 weeks and then if she hasnt made contact then you will with her to discuss how to proceed with the seperation, or reconciliation should that be the decision.
Once away you can either sit there dwelling on what will or will not happen or you can try and move on as you would should you and your wife not be able to reconcile. It more than likely wont happen, but some genuine time apart, with no contact might make her realise she does love you and she made a rash decision by telling you its over.
If its over, and she hasnt contacted you, and then you contact her, meet somewhere public (lunch/dinner is usually the best) and discuss a fair split. My mate decided to allow his wife to keep the family home because they had children involved, and as she was a housewife he advised he would pay the mortgage on the house for the 1st 6-months while she found a job, but said that after this 6th month he would no longer contribute to the house. If she didn't have a job, and therefore couldn't afford the mortgage, then they would sell. If she could afford the mortgage he is going to hand over his share of the house. It will leave him well out of pocket, but gives him a 100% clear break.
The other option the discussed was to sell the home, clear all debts, regardless of who they belonged to, as even though the debt was in her name, or his, they both technically during their marriage contributed to it. Whatever was left they split equally. However, because of children, and her family living too far away, they decided against this for the time being.
As above, should you wish to talk to someone anonymous I am willing to lend an ear.
Good luck, and although its not an easy process, it will get easier in time.