This is definitely a tightrope we walk as providers. Because of the intimate nature of the service Iprovide, the cold detachment just doesn't feel right to me. Especially since my general approach is to cultivate regular ongoing situations. A personal connection of some sort becomes inevitable. Especially as you learn to navigate a regular client and his desires, quirks, hangups, insecurities, etc. You have to do it with a degree of empathy. You can't leave your humanity at the door when you walk in if you genuinely get off on providing a client with a top shelf experience.
All that said, boundaries are of paramount importance. And you find opportunities to assert those whenever you can.
As a bona fide gym rat, I find myself observing the relationships that clients develop with their personal trainers, and sometimes it seems an apt parallel. These folks spend enough time with their clients to really get to know them, and real friendships can develop. But the framework for that friendship is always there: one is paying the other for a service that makes their life better.
I often have regulars text me on off days/hours. Usually it's a reference to something funny we talked about. I was initially unsure of how to handle this kind of thing. But ultimately, we're humans who have a regular ongoing interaction. So I do often engage, but I'm careful of doing it immediately. Happy to engage, but you don't get my full immediate attention until it's our designated time.
To me it's all about ways to maintain boundaried connections.