Sorry to hear that mate, and sorry to hear about the rainy life weather you're experiencing at the moment. Are there any support groups for divorcees? I know that might sound weird, because only alcoholics or cancer survivors or such like might be thought to need them, but I do think that the end of a relationship can sometimes bring on feelings not too dissimilar to bereavement, although obviously not comparable, an absence of someone who means so much to you is an absence all the same, and it is in that absence that feelings of melancholy fall.
Try and find a structured way of getting out into the world in interaction with others, where you can meet people. Your NHS counselling will help with that. When you get back into employment that will help too. But in the meantime be proactive in looking for any kind of support group or medium in which you can work through things.
http://www.divorcesupportgroup.co.uk/support/groups/The only problem with this is that they charge money and if you're skint that is an issue.
The NHS counsellors or even just your own GP might be able to point you towards something along those lines.
More generally, now is the time to walk out of the door. The walls of your house can easily become to seem like fixed walls inside your soul. The importance of activity and motion cannot be overstated. A routine to take you away from physical confines is important. You only discover roads and routes and paths when you go out into the forest. Hook yourself to things externally. Have you thought of returning to college or university? You are a very intellectually gifted person. Self esteem and fulfilment can be achieved by channelling that gift towards an endgame of formal study.