So next step will be to work out her budget, and what kind of appartment she can afford. If she's decided that she absolutely wants to separate, she should be able to support herself. Other people with the same job in the same city do it.
OK, good deal. One very common mistake newbies make here (esp. us "fixer" men!) is to try to shelter our walkaway/wayward wives from any consequences of their walking away. It's best to let them find their way, and to give them space (while not directly paying for them to conduct any affair).