I am very sorry to tell you but the woman you think is coming to marry you is a romance scammer that you will never meet. She is lying to you to get money from you.
What makes me say that? Because nobody needs any money at all to leave Ghana
. All this person needs is her passport, a visa if one is necessary for Mexico, and her plane tickets.
Anybody who tries to tell you that the Ghana authorities want money to leave the country is a liar.
You don't have to believe me. The Ghana Immigration Service itself actually warns outsiders of this scam and makes it clear that there is no such thing as a Basic Travel Allowance or a Declaration Fee. These "requirements" exist only in advance fee frauds. You can read the warning for yourself on the Ghana Immigration Service's website here.
It specifically says that no money is necessary to leave Ghana.
The US Department of State's warning is even stronger:
"Beware of anyone who requests funds for a BTA, or Basic Travel Allowance, as a requirement to depart another country for the United States. There is no such thing as a BTA
. In other cases, your Internet friend will claim to need a travel allowance, or travel money, to be able to travel to the United States. Again, there is no such requirement . . ." You can read our governments warning about this here.
Cease all contact with this person. She has given the whole game away by asking for the one thing that categorically proves her a scammer.
If you have already wired money via Western Union or Moneygram to help you "fiance" get to Mexico, you are the victim of a crime. Report it to your local police and national police. The only chance you have of getting your money back is if law enforcement can find her and her buddies behind this fraud and bring them to justice
I am very sorry to be the bearer of bad news.