If it was legal, people will complain that the gullible and simple minded are being misused, brainwashed and abused. If it was illegal, we have people like you that will complain. Again, she's most likely lying about being forced into it. 90% of prostitutes will tell you they were "forced" once exposed and caught, even during the act. It's a self defense method to keep herself relevant in the outside world and to also be able to move on with her life and leave doors open for marriage.
If you had any experience in life, you wouldn't need me to mention this to you.