How good is your spanish? you may be looking at Living IN MEXICO with your wife for the next 10 years...
Your wife is subject to a 10 year bar from returning to the US since the date she left. Because she entered illegally (without an inspection) and you provided USCIS proof of her illegal presence (namely marriage certificate).
I would advise you to find a good lawyer and perhaps he/she can help you get a waiver for your wife. Do not go back to the ones that told you she should leave. (Did she leave by plane anyways? or across the desert?).
Do you have any children together? that may help the case.
DO: Atlanta, GA
Year 2007
5/03: I-485 Receipt Date
8/07: I-485 Approved
8/27: Conditional GC Received
Year 2009
5/15: I-751 Receipt Date
9/22: I-751 Approved
10/3: Unconditional 10yr GC Received
Year 2010
5/10: File N-400 for US Citizenship