Urgent help required with non-resident alien

Help!  I have a US tax question and I hope someone can help with an answer.  I am a ukc living in the UK and I got married to my fiancé in the USA July 2010.  We have been living separately since then because my usa wife has been taking care of her father with terminal cancer and her son was finishing up his senior year in high school.  She is currently doing her taxes and is confused on how to file because we are married but living apart.  Her in the USA and I here.  We have not made the decision yet on where we will end up but we don’t want to mess up anything if we decide for me to move over to the usa in the future.  How does she file? Married filing separately? And what about a SSN for me? She supports herself and I contribute nothing.  Please help.

Thanks

Andrew

Married filling separately.  If you don't have a SS# then she can put NRA, for non-resident alien in the blank. 

thanks for the info...

Do I need the ITIN number also, as the last thing I want to do is mess it up for future tax returns?

No, only if she wants to claim married filling jointly.