My loyal reader may have noticed that I am, once again, writing a lot about mental illness and depression. There is a reason for this: I’m having a bit of a dip at the moment and it helps to write about it. It’s not like my pre Christmas dip, when I managed to break down in front of some of the heartless management bullies at my then employer Tesco, who reacted to my deteriorating condition by stepping up their bullying and unpleasantness. But it’s a dip nonetheless that I saw coming, as I usually do.

Now that must seem odd to the non-depressive. How on earth can you foresee a bout of depression in advance? And if you can, why don’t you do something about it?

To the first question, the answer is simple: I know what it feels like when the black dog is arriving. I know the signs. I can feel myself getting lower, I can feel my spirits sagging, my optimism disappearing, I feel hopeless and inadequate, my sleeping habits become more erratic and, frankly, I feel like shit. And I find myself on the edge of tears, often very suddenly and for no obvious reason. I want to be alone but then when I am alone, I don’t. I want to go somewhere, but when I get there, I wish I hadn’t gone. That sort of thing. Other tell-tale signs are available. To the second bit, there is nothing I can do about it. I have had so many different types of treatment, including Cognitive Behaviour Therapy (CBT) which kind of worked for a while, but I have long recognised that I am not the sort of person who has a particular type of treatment and then all my problems go away for good. All the techniques I learned are all well and good, but when depression rears its ugly head, they are useless. I need talking help as well as chemical help and increasingly help is harder to get.

I am on a waiting list, as I have said. Not the NHS waiting list because that’s so full and I might die of natural causes before I ever get treatment, so the NHS employs private companies to provide therapies at huge extra cost and now I am on their waiting list instead, with no timescale as to when I might be seen. But I am one of the lucky ones. I am not regarded as a suicide risk, nor a dangerous self-harmer, but I know for a fact that there are those, with the potential for catastrophic outcomes, who are waiting too, waiting without a timetable, waiting without, it has to be said, hope.

It was hard enough for me to get a GP appointment with my chosen GP – impossible, actually – so I wrote her a letter explaining that whilst I did respect the other doctors in the practise who were obviously able and competent, each time I saw a new one, I had to go through all the hassle and stress of explaining my life history in an environment where you expect the doctor to have a buzzer for when your time is up. Some doctors might as well tell you to hurry up because they have more important things to do. Happily, some weeks later, she called me and made me an appointment, there and then, to go to the surgery. (It was a few weeks later because the reception staff didn’t get round to forwarding my correspondence straight away. Well, depression is not that important, is it?)

She was terrific when I did see her, recommending me various therapies, giving me contact details and doubling my medication. I have to call her this week, assuming I can ever get through, to tell her how I am getting on. (Answer: same as before, just getting by.) Doctors, by and large, do care. It’s the grinding bureaucratic inertia that gets them down, just as it gets me down.

The worst thing is we depressives don’t see an end to it because, ugly and destructive though it is, depression is somewhere we know. We almost feel secure in our depression because it is a certainty and life without depression is almost unimaginable. By a huge paradox, our mental issues are our comfort blankets too. How mad is this?

I would not wish this on anyone. Of course there are others far worse off than me, with far worse conditions and far worse prospects and that brings the guilt factor. Why should I feel this bad when so much of my life is good? How can I tell someone that, yes, I am not short of love and support but I am desperately short of self-worth and satisfaction. Forget what you think of my achievements, whatever they are. When I look in the mirror, I see an unqualified failure.

I am the happy depressive. I know how to smile through an episode, so you might never notice, unless you live with me, that is. I have recently, for the first time in 25 years, considered the effects of this dreadful illness on my partner. To my deep shame, it had never occurred to me that it might actually affect her life, but of course it does; a lot. It had not occurred to me, from within the selfish depressive bubble, that I might be a very difficult person to live with, and it turns out that sometimes I am. But then I can turn it on when there are others around. I can be the clown, the joker and sometimes something sort of clicks when I am in the company of others and I can compartmentalise the black dog. I can smile through the gloom, laugh through the darkness, when the mood takes me. And I am glad I can do that because it makes life worthwhile. If I couldn’t, I’d be struggling to justify the struggle for existence.

Yes, I am writing a lot about the black dog because he’s here right now and he’s pissing me off. My legs and my head have been incredibly heavy the last few days and my brain has occasionally become a kind of papier mache muddle but, if things go true to form, some semblance of normality will soon return and I can resume raging about Katie Hopkins, David Cameron or anyone who gets themselves called Reverend.