I like others have had a varied experience with counselling. two lots of relationship counselling, one with Relate after my husband's infidelity - the counsellor would get irritated because we weren't shouting and screaming at each other, so in the end we stopped going. Also, she kept focussing on why I found the infidelity so upsetting (married less than a year!) and glossed over the reasons why my husband might have done it.
The second counsellor was years later, while we were splitting up. She helped us to sort out an amicable split, so we were able to manage it with the minimum of rows, upheavals etc and without traumatising the children more than necessary. She was fantastic, we both felt safe with her, and she helped us both to explain our feelings and actions to each other.
After my first child was stillborn, I was (obviously) terribly sad. The GP referred me for counselling, but I only had one session. The counsellor was very understanding, but said to me after we talked for a while, that what was going on was simply grief - I was responding in a completely normal way to a horrible tragic event. There was no need for counselling, it was time that would heal. That was fine with me, I had family and good friends I could unload to.
So, anecdotally, I would agree with others that some counselling is absolutely spot on and others not, and the character of the counsellor is very important - something that's hard to find out in advance..