So today I came out to my girlfriend of 3 years, I kinda had to. Anyways long story short she said she doesn't care, "You could be a 600 pound racists and i would still love you" her words aha, she immediately came up with the idea that we should get married. We kind of are basically "married" without the title we don't live together but that's because her dad won't allow her to move in with me until we are married or engaged.

So my question is, I know my chances are slim I've tried to look into it but never find anything clear.
Would marrying her allow me to legalize my status be it by getting a visa, green card anything.

I am a 20 year old Dreamer, I've been in the US Since I was 2 1/2
She is a 19 y.0. US Citizen.

Any info guys?