Counselling isn't necessary when gambling isn't rooted in you, and cancelling your internet connection isn't a good idea. Most of our communication now pass thru that, so cutting it is like getting alone in the four corners of your room. If you are willing to quit, no need to force it, as long as you are aware that you are addicted, you can remove it slowly. But that's right, you need to decide, that's the hardest thing "to begin".
But it seems that gambling is our topic here so I would say that counselling is really needed. Because in case that someone needs help in able to overcome his weakness, counseling is what he need. As long as he will follow what is the counselor will say or else counselling will be worthless and with the cancelling with internet connection that will not help either that will make you even worst.
As I've said, it is not necessary if gambling isn't rooted in you. That means you are still conscious on what is happening to you. Nowadays, DIY is very common, a research and trying it out to your self will work. Also going out and breathing fresh air away from your computer could help you think on what to do and where to start on quitting.