How do you prevent yourself from falling in love with a prostitute?

Drop her a message, tell her you would like to speak to her just a chat no sex. Offer her a little bit like a bit of bait. Not as much as you might pay a reasonably priced personal trainer in a gym,  'cos she doesn't deserve that just for a conversation, but let's say one would pay a personal trainer $30/hour  offer her $20 for an hour to chat with her. If she says no to the chat then that should influence you away from her. 

If she does take you up on the offer then consider this.. If she charges $150 an hour for sex, then why is she willing to chat to you for $20 for an hour.  It tells you how much she dislikes sex with you and would much rather sit at a distance from you and have a chat.  (and don't think it's to get to know you more - she has had enough time for that if you've been seeing her for quite a while).

Let's say she accepts. So now you get to interview her, interrogate her, find out what's really going on.    If she has said something that suggests she has an attraction to you, but said or done other things that suggest she doesn't.. So  The simple fact that she doesn't freely choose to be with you.  You can question her on that.. Ask her what it is that attracts her(if she lists things you can't add up to or says she only has attraction to guys for a few months, then at least you know she's not lying, and you see she's not attracted to you).. And you can pick up on the things that she has said to you that don't add up , and question her on them.   She might try to BS you saying if she does this for one guy she'll have to do it for every guy otherwise it's not fair.. that's not true , you might already know that some guys get more than others.. And of course if she wanted to make exceptions she could.  The simple fact that she doesn't freely choose to be with you, questioning her on that can bring out a lot of truth. She is unlikely to freely admit to lying.. or to characterise her behaviour or words as lies, but if you poke out a blatant misleading statement or act, you can say to her "I wonder how much of this is all an act".   She might actually admit to that and justify it without blinking an eyelid.   Now, let's say she tells you that shes spending time with you and is happy to give you the $20 back.  Tell her that's nothing, that's no big deal.. She can keep the $20. But if it was $150 I doubt she'd give it back, tell her that, and she may even admit that eys if it was $150 she'd keep it 'cos it'd help go towards a holiday.   Really interrogating a manipulative whore at little to no cost to yourself can be very amusing.

It may well be that hugging her has been something that has given you tremendous pleasure..  She may know this, and use it to trap you.. You can tell her that you can't hug her, you can give a true reason.. maybe.. that if you hug her it'll be too hard to get her out of your head. Or maybe you're not happy with her 'acting' and you don't think she deserves a hug. I've only tested the former.  At the end of the meeting she might holding out her arms for a hug. You can say, "Sorry, I can't"(not like boo hoo i'm sorry, but a strong i'm sorry), and turn around, back straight, walk away.   or perhaps "No, I can't" and walk away.  It'll probably be a gift to the next guy.   Maybe another day a guy will dump a girl and it will be a gift for you.  That is a good way to dump a manipulative whore, but also to learn a lot in the process.  

You can train yourself when you think of hugging her, imagine holding her at a distance from yourself at arms length and not let here near and say "you don't really want to be here". See, you know that when that hour is over she'll be off. There are dozens of things she'd rather be doing than be within your arms (Despite her acts to the contrary).

Yes she'll have $20 but that's not really much of a win for her, she knows she has most likely lost a client and that she'd be more likely to see you again if you had accepted the $20 that she was willing to give back to you.   She got kind of dumped, and she has a mere $20 from a customer that was paying $150 an hour. And of course, if she ever wanted to see you freely, then she can call or msg you, but she won't, 'cos she never really liked you much or at all anyway, despite the possibly watery eyes or the false words or groans or passionate gasps when embracing. She's a fraud and you should be glad to have gotten rid of her so well.   If her eyes did water, and it wasn't an act, then maybe it was feeling sorry for you, but when you walk away from her and leave her, she'll probably respect you more than she ever did when you paid $150/hour to see her, and she'll find another loser.