How Can My Colombian Girlfriend Get a Tourist Visa

i am a us citizen,,born in US. met a girl from the mountains in colombia 3 years ago. got to know her and i may marry her but we have never met. we talk daily and have 3 years of facebook proof. i cannot leave the states due to child support arrears.(long story). i know next to nothing about this stuff. she is very! poor. she has no job as she lives in a tiny mountain village in coffee country. she is still married but seperated over 5 years. she has a son 16 and a daughter 5 years old and lives with her mom.
i would like her to be able to visit me and take it from there. i live near new york city. she also has a long time friend very close to me .he is married and lives 10 miles away.
so what is the best way to go about this. she has no bank account. should i write some kind of letter sponsoring her visit. do i or she mention the truth about our relationship and that we might get married in the future if all goes well and i apply for the engagement visa? is it best to tell about us or try to get her friend to help. i am copletely lost here. should she try to visit with her children or 1 of them or none. i understand the embasy wants to feel secure she will return home afterwards. how long a visit should she request and should she have a bank account or a sponser letter. if so how much in the account and how does she explain how she go it if i give it to her?
she wants a divorce from the ex as well. thanks in advance

You can likely forget any chance of her ever getting a tourist visa. She cannot be your girlfriend, you have never met her. She has no significant ties to her home country. Is a booty call for citizenship really more important than paying for your children?

OP, you are absolutely crazy to pursue this. She is not even divorced. You are her ticket to the US - and look at what will happen to you on the basis of the affidavit of support when she leaves you.

Rather than trying to pay for a visit to the US for her (she may become an illegal overstay by deciding not to return home), look into professional help to understand why you would consider someone who is marries and whom you have never met in person is your "girlfriend" and the legal and financial ramifications of your actions. Once you put money into a bank account for her, it is hers and gone.