Without reviewing your contract it is hard to give a definite answer. Assuming all inspections and contingencies have been satisfied, your way out is limited. By walking away you will likely lose your earnest money deposit. Also, if you signed a brokerage agreement, you may be liable to pay liquidated damages to your realtor.There may also be a liquidated damages clause in your purchase contract.
If you and your wife are separated, it may be possible that your ability to get the loan is hindered. In some contracts the purchase is contingent on financing. If you cannot get financed without your spouse then you may not be breaching the contract.
My advise is to continue to discuss this issue with your realtor and carefully review your contracts.
Note: This answer is for general information only and does not constitute legal advise nor does it create an attorney client relationship.
Answered on Jul 14th, 2014 at 8:30 PM