Many in this forum have either the same experience or went through similar ones as you OP.
The reason why we engage sex workers is because they are sexually attractive. And that in itself is why we want female's attention in the first place (to get sex). When the sex is good - we get hooked, and its a slippery slope from there.
Having sex is their job. It's really that simple. As humans we find it hard to disassociate sex and intimacy. Our minds simply go haywire when the target of our affections is having sexual relations with another. We are not built like that. No matter how good is it one day you would remember about how good it was. It seldom lasts and often the happy endings stops in the bedroom and not ever after.
Enjoy the sex and company but do not envision anything more. If you find it tough to maintain a transactional relationship - my recommendation is to find others as a replacement
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