There is a big emotional and psychological toll to be used by another person for money.
Again, you're literally doing this if you have a job. I don't disagree. You just only have an issue with sex. If you think this is valid, explain why sex is different.
How do you fix crippled mental health?
That's part of why we have so many issues in the US. People are selling their lives to corporations to survive, and they're given no mental Healthcare to help them. Mental Healthcare is a thing though and it can be provided.
You think someone who has been used over and over by other people for their own pleasure is going to be in better shape than that emotionally damaged person? Absolutely not. NO ONE comes out of sex work undamaged - its literally the price of participation.
No one comes out of capitalism undamaged. There are some porn stars and brothel workers (with protections) who seem to be perfectly healthy though. It's the lack of safety nets and protections that cause issues. The same thing is true for factories before we had safety nets, or any other kind of work. Sex work is work, and all work needs protections so workers aren't abused and taken advantage of. Without it, of course there are issues. Its not because of the type of work though, it's the lack of protections.
You have a weird issue with sex, where you think it's "being used" if you have sex. I haven't done it for money, but I've had plenty of loveless sex, and it doesn't have any magical powers. It's just an act.
We're all being used every day. There's no difference when it's sex. You keep saying there is, but providing no reasoning other than just that it's true because you believe it's true.
There are a lot of sex workers who get through it all and are as perfectly healthy as the rest of us, sometimes more. Yes, there are some who don't, but that's true for everything. Sex work has the double issue of a lot of it not being legal and having no protections, and also attracting people who aren't as well already. We should be doing more to make it legal so we can help them, not the opposite. Making it illegal doesn't make it go away, it only ensures the issues you're pointing out are more common.