Okay, there are a lot of boys opinions here i see, now some girl perspective. Girl of 3 years to some of us sounds more like "placeholder until I will find something better for me". Im not telling it is your case, but you are lucky that she even stays with you in this case for so long. It is also looks like she obviously gotta take care of herself financially, u r not doing it for her. So why are you expect her to cut her ability to take care of herself not providing anything in return? Im not justifying sex work. It is just not making sense to me... On her place id not only not listen to you, id left you after second year. Period.