Interesting post OP. You express yourself very well and I've enjoyed reading.
My honest take on this (which I hope doesnt sound scornful - not my intention at all) is that there's an element of immaturity to it. That's not to say you (and the many others who clearly experience this too) must be young, or that only young kids get EAS. But I do suspect an emotionally mature man is much less likely to.
You're only there for an hour or two (unless you go for overnights - which seems unwise at best if you're aware you have a predisposition to feeling this way) each time. And as nice as the girl may be, as friendly the exchange may be, it's undoubtedly a business transaction - how could it be mistaken for anything else when you don't even know her last name and pay her to allow you access to her body? It would be different if you'd had an opportunity to really know or come to value something about her, but what are these feelings based on - isn't it fundamentally her body and willingness to satisfy your needs? Unless you are paying just to meet/talk, without also 'using' her, I'd suggest so. Having your needs tended to in an expert and charming manner can be enchanting, for sure - but it's a much less pure and actually far more self-centred thing than love. I guess we might call it infatuation, as opposed to love - but I'd suggest that it's a shallow and illusionary emotion.
As good as the service may be, sex is only a physical act. There's no meaning attached to it inherently. Developing genuine feelings for someone goes beyond the physical (and transforms the sex you have, by ascribing meaning to it). Such sex is fairly unrecognisable from the sex that you have with a prostitute. Perhaps this prossie gives great OWO for example - and great head is really great, don't get me wrong - but it's what she does for you that you 'love' (and/or how it makes you feel - which is still about your needs) not the person providing it. This also partly explains, I think, why you as a customer are consumed by jealousy - whereas, if a prossie is in a relationship/has a partner, that person may actually be more able to accept her job (since his feelings for her would likely transcend the physical).
I link this all to maturity mainly because I think that's what enables a person to see and appreciate things in their true context.