Am I Being Told The Truth????

What is the name of your state? North Carolina
I have being dating on and off (not seriously) this guy for a while, he and his wife were"seperated" (not legally) months before we even met, they have children and got married in the state of Illinios, She now lives there with the children and has been living there apart from him for over a year and a half, and he lives here,.... She is not a US citizen yet,.. but the paperwork has been in the works for a while. He is a US citizen, and so are the children. My question is, he told me he could not get divorced until she was a legal citizen. Is that right?

I'm married to a foreign national, so I may be able to answer this.

I want to get some terminology straight about immigration status. A person who immigrates to the US through marriage to a citizen is first given "Permanent Residence" status, which is almost the same as citizenship. If your friend was married for less than two years before his wife came to the US though, her residence is "Conditional" for (appoximately) two years. The conditional part is a time period to verify that the marriage is valid; if divorced she would most likely be deported.
After at least two years of conditional residence, they have an interview with the INS to remove the conditions and she becomes a full permanent resident. This can take much longer in some states though. Once she is a full permanent resident, they can divorce without any problems.
Citizenship is another matter entirely. Marriage is not required for citizenship, but does make things easier. She could begin naturalization earlier if married (after 3 years of permanent residence instead of 5 years). In general though, a permanent resident can't be deported unless she commits a serious felony.
I suppose her citizenship could be denied if she divorces while going through naturalization, but she wouldn't be deported.