My first instinct upon reading this is to think, "Ouch, burnout" - but please don't think I mean anything personal by this, as of course I do not know you personally or anything about the full details of your situation, and of course I am not trying to tell you what to think!
So I'll admit straight-away that I might be well off-track (just ignore this post if so!) but your post sounds to me exactly how I feel during even quite mild burnout. Sometimes burnout is described in quite a jolly fashion as, "Oh, you just need a little holiday!" but I find that the emotions involved can be quite painful and difficult to deal with. Is there a chance you could be working hard despite perhaps feeling that you could do with a whole day (or month!) to yourself? And maybe you could be ignoring this feeling because you don't want to feel lazy/selfish? I know that I hate that random week I get occasionally where I just can't answer my phone or accept bookings and I don't know why; I feel very negative ("How can he expect me to do that for him? Ugh! They all need to keep their penises away from me. Argh! So many needy men. Can't they see their wives for once?!" and so on) but when I realise it is burnout, it's almost always a huge relief. It's not that I've suddenly turned into an evil manhater who can't bear to be touched by anymore pokey, grabby fingers - it's just that I need a little time off to refresh my brain and body. Sure, I bet some women are amazing and never get these feelings, but I do know that it's not at all uncommon!
And basically, in answer to your question, yes - of course I let my clients latch onto my nipples if they want, and finger me if they want; as long as they don't cause any pain, of course, I just throw myself into it and try to be as positively responsive as possible. But... that's when I don't have burnout, and the job seems very fun and rewarding.
It's hard because I could never even manage to be a full-timer at this; more than a few appointments a week and I'm knackered, and more than one a day and I can barely muster a polite smile when I buy the bloody Big Issue. I know this whole post probably sounds really awful and negative but I've always tried to be up-front; I don't take bookings unless I feel really positive (cos otherwise the consequences would be dreadful!) and I never really planned to be a long-term full-time prossie, only to make the most of my experiences and be thankful for the brilliant chance to study
and pay my rent at the same time. And I definitely don't think any sort of burnout or low-work-tolerance means that you hate men or clients or any of that sort of thing - it's only a natural tiredness from "giving of yourself" a lot.
And that might all be entirely the wrong sort of answer, so forgive me if it is.

You just reminded me of myself at certain times and if this is the case, you must be kind to yourself; it's very important to not try to "push through" and definitely not to blame yourself for anything!