She does not need to file a return. The W7 is used to apply for an ITIN. If she does not intend to apply for a tax identification number, this does not need to be completed.

If your spouse does not have a SSN or ITIN, you cannot file a joint return. You can file your US tax return as Married Filing Separately, and just report your own income there.  TurboTax can walk you through this process, and help you create the necessary Form 1040.  If your spouse does not already have an ITIN number, or a Social Security Number, then this return would have be printed and paper filed.  If your spouse has a valid ITIN or SSN, then the tax return would be eligible for e-filing.

If there is no ITIN or SSN, then in any place where the nonresident spouse's taxpayer ID number is required on a tax form, you would take a black or blue pen and manually write "nonresident alien" or abbreviate as "NRA."  In the TurboTax software, you can input any "made up" SSN or ITIN you want to, in order get through the program (we suggest 999-88-9999, 999-88-9998 or 999-88-9987, as those numbers won’t produce any TurboTax program errors in a review check) as a temporary "placeholder.”  You can then later "white out" that number when the paper pages are printed.