You better enter brazil as a tourist and then get married. Im sorry to tell you this, but there is no way you can have a "girlfriend" visa. Just as it does not exist in France or in the US, it does not exist in Brazil either. the visa you refer to is in place for same-sex-marriage or partnership rights, as in it gives options to same sex couples who in many areas are not legally allowed to get married. you have the legal right to get married, which is virtually what this visa is an alternative for.
The immigration process in Brazil is very stringent and many are surprised to hear that. The only visa you can enter on (as in the Brazilian consulate gives it to you before you enter) based on family is called the family reunion visa, which you do not qualify for. There is no way around this.
I married one year ago so i could get my permanent residency. i am only 24, marriage in this form is a legal route to be with the person you want to be with. it has to be that important to you. WE ALL have to go through this. all of my expat friends (there are many who are in the same situation whether from the US, Ireland, India, Canada, it's all the same) had to make the choice to get married, male or female immigrant. you legally marry, you dont have to do a wedding. but you cannot get a green card as a girlfriend, the Policia Federal would never allow it, particularly since you are together only 2 years and have the legal rights to marry.
your only option is to come as a tourist. stay 180 days, then leave 90 days, then stay 180 days, then leave 90 and repeat. You can do this but you cannot open a bank account and get a driver's license as a tourist.
if you eventually are sponsored for a work visa, then that can turn into residency.
For now, enter on a tourist visa and make your decision after that.
If you think you still fall through a loophole, your only other option is to speak to an international immigration attorney, preferrably one in Brazil.
good luck to you all, but my best advice is to just get married. it's a piece of paper, think of it as that. it is the quickest way. one year after marriage you will have your permanent resident card and all the rights it carries. send me a message if you have any questions about brazilian marriage process and federal police applications after that 