A counsellor is someone who will sit and listen to you, someone who will nudge you when needed and possibly guide you in reaching your own conclusions about what you need to do. A therapist can work this way too, however, that all depends on what kind of therapist they are ie. a psychotherapist or, analysts (as they are known in the US). Psychotherapy is hard work. Often, it involves multiple weekly sessions for a number of years as the idea is to find the root cause(s) of your problems. There's also Psychodynamic therapy, something I tired and it wasn't for me.
I suspect you just need a straight forward counsellor. I saw one privately (I paid) for quite a few years and it was hugely beneficial. However, it is incredibly rare to find a straightforward counsellor on the NHS as the therapy they push is Cognitive Behaviour Therapy which I am certain is not the kind you are looking for. (This is therapy's aim is for you to change your own behaviour). Also, be advised that on the NHS, the waiting lists can be long and you only get a set amount of sessions.
If you do decide to pay for therapy, then you will be able to find a sex worker friendly one. Your dynamic with your therapist is essential and if you do decide to enter into therapy, make sure you keep looking until you find a therapist you click with. I would advise you contact the British Association for Counselling and Psychotherapy as they will be best able to advise you further.
One thing you must understand is that the majority of therapists works to a schedule. They will expect to see/speak to you at the same time and on the same day every week. This is for your benefit too. They want you to commit to your therapy and why they insist on working in a certain way. Very few, if any, will make an exception and see you ad hoc.