How hard is it going to be for my foreign born girl friend to travel with me as I teach at international schools around theworld

Hello, I'm an American with 7 years teaching experience. With 3 of them at an American International School in the Dominican Republic. I'm planning on continuing to travel and teach internationally. I fell in love with a girl in the city I teach in the DR. She runs a non-profit and also is a teacher. Just not certified in the USA. I'm wondering how hard is it going to be to bring her with me on my next contract? If I marry her will she be able to travel with me as a spouse or with a green card. Does anyone have any thoughts or ideas. Thanks in advance.