I married a man 2 years ago. We had lived together for 4 years prior to that. He has 2 daughters. There mother has not been in the area for several years. Twice a year she will see the children for a few hours. The girls were raised by their great grandmother in the projects. When I came into my husbands life, we brought the girls (now 11 and 13) to live with us. Their lives blossomed since we were awarded custody of them. 7 months ago, my husband left me and the girls for another woman. I was fired from my job from harassment from his girlfriend. I get no support from him for his children. I am the only one who has ever cared about these little girls. Not legally mine, but I feel like they are. What can I do? Can I get assitance or any help at all? They want to be with me. They call me mom, and are afraid of losing me as their only parent. Please help.

If you didn't adopt them then you need to go to court and get gardianship right away. At that time you can request support.
Has anyone tried to contact the bio mother?

Child abandonment laws do not apply. They refer to leaving a child without ANY supervision.

However, abandonment may be used as grounds to get custody. Since you currently have no legal right to the girls, you need to apply for temporary guardianship immediately. You then need to apply for a divorce and support.

When you say "we got custody" did you adopt the girls, or did HE get custody.

It sounds like the girls are with you? If so and you did not adopt, you have no legal rights to them, and could not even legally take them to the doctor or put them in school.

You will need to see about guardianship