Separate tax return: Can she do it?

What is the name of your state? FL

Hi, me and my spouse are currently separated. For the year of 2002 we agreed to file a joint Tax Return. She is an accountant so, I gave her all the documents, W2s, mortgage and etc.
Well, after our recent fight she got pissed off and now saying she will file a separate tax return and claim to be a head of household (she has a daughter from previous marriage) who live with us.
I am completely against the separate tax return (I'm in a higher tax bracket and for INS reasons).
Can she do it without my spousal agreement. Can I file as a head of household since the whole family been living together and we both were taking care of the child? What can I do to go with joint return not separate?
Her reasons are - she will get a tax refund and will have money to pay for a divorce. She needs a divorce - fine, I will even pay for it. But the return needs to be filed jointly - it's imperative.
Please give advise. Thanks.

"Can she do it without my spousal agreement."
*** Can she do what?? File separately?? Yes. File as head of household?? No.

To qualify for Head of Household filing status, the following five tests must all be met:
1. The taxpayer is not married at the end of the year. (There are exceptions to this rule that I'll discuss at the end of this article).
2. The taxpayer must maintain a household for his or her child, dependent parent, or other dependent relative.
3. The household must be the taxpayer's home, and the household must also be the main home of a qualifying relative (as defined in #2 above) for more than half of the year. (Again, see the notes below for additional discussion of a qualifying individual). There is an exception to this rule: A dependent parent need not live with the taxpayer; however, the taxpayer must provide more than 50% of the cost of maintaining the dependent parent's separate household that was the parent's main home for the entire year.
4. The taxpayer must provide more than 50% of the cost of maintaining the household.
5. The taxpayer must be a U.S. citizen or a resident alien during the entire tax year.

As you can see, she fails to qualify on several counts.

"Can I file as a head of household since the whole family been living together and we both were taking care of the child?"
*** As you can see from above, no.

"What can I do to go with joint return not separate?"
*** File first. But to do that, both parties are required to sign the filing. And since she refuses, you simply can't file jointly without her permission.

If you're in a higher tax bracket, file MFS & claim your stepdaughter as a dependent. You probably paid more of the kid's support than your wife. Indicate that the child lived with you for more than 6 months during 2002. This will raise red flags & prevent her from filing HH.

Thank you for your response and info, but there is more to that story.
Here is new information, go to:

https://forum.freeadvice.com/showthread.php?s=&threadid=132859

Thanks.