Looking back on when my mum died several years ago, it would be easy for me to count every time I thought she might live as a moment of stupidity. She had stage four lung cancer. Even with the best treatment in the world, her chances of getting through it were minuscule. But that didn’t stop me from crying tears of joy when, a few weeks after she started immunotherapy, I saw a scan showing that the tumour had shrunk. I tried to stop myself, but images of her – strong, and loud, and cackling her head off again – flooded my mind. Anxious people know what it is to be a slave to the eternal “what if?”, but what if the “what if” is about everything going right? Even as I held her limp hand in the ambulance to the hospice, a microscopic but irrepressible part of me thought a 180-degree turn was possible. She was still my mum; she still said “fuck” a lot, and loved us aggressively, and had red hair, even though the grey roots were slowly taking over. But yes, it was deranged – at this point – for me to hope for anything other than an end to my mum’s pain. But sometimes “deranged” is exactly what you need. Optimism gets a bad rap. Sometimes rightly so. This year, obviously, optimism has been partially responsible for a lot of idiocy. “It’s just flu,” said the optimists, as they continued to lick handrails well into April. And of course, there’s been a lot of dangerously optimistic rhetoric (sincere or otherwise) from Boris “let the plebs die of Christmas” Johnson. Optimism can be a gateway drug to either recklessness or passivity. But the year my mum died – and once again this year – I couldn’t have survived without it. In the last month of the cursed year that is 2020, the urge to tell myself that everything is basically going to be OK has become a need. Unfortunately, this does mean (internally at least) screaming “SHUT UP” at every well-meaning, scientifically minded person who brings up potential difficulties in the post-vaccine Covid world. But it also means being able to get through days, and even weeks, with the minimum number of depressive breakdowns. “I have a good feeling about next year,” I heard myself say to the dejected looking barista at a local cafe. As much as hearing those words come out of my mouth was like an out-of-body experience (and as much as I immediately regretted it as thoughts of the virus developing the ability to shoot guns seeped in) I clearly needed to get my optimism off my chest. Even if the barista didn’t seem convinced, and I had to panic about having come across like someone who had recently joined a cult. After all, Boris Johnson did kick off this hell year with that “This is going to be a fantastic year for Britain” tweet. Which quickly became a meme about how precisely un-great a year this has been for Britain (or the rest of the world). His double thumbs up in the accompanying picture crystallising the irony into something truly grotesque. But if optimism is a drug, then using it sensibly is really all about the dosage. Like my antidepressants, optimism should be taken daily, in the correct amount. Too much could kill me, and too little would send me into a ditch of withdrawal. Optimism needs to be balanced out with reverence for bad news, but it also needs to be enjoyed for what it is. Thoughts of hugging my friends, or masklessly huffing the smell of baked goods in Sainsbury’s, are medicinal. I also appreciate that actual medicine is medicinal, and if those making it are telling us to manage our expectations, we should probably listen to them. Is it true optimism, though, if you know you’re deluded? Well, no one would buy lottery tickets if there wasn’t a teeny bit of them that thought they might win. Optimism, I find, is often about the fantasy of things going right. When I buy a lottery ticket, I essentially pay £2 to spend a few days living – in my head – the life of someone who just won tens of millions of pounds. I buy a house and some incredibly expensive kitchen knives. I eventually have an existential crisis about having been allocated a vast sum of money at random (optimism is fairly new to me, and I’m not always good at it). When my mum was very ill, my thoughts would often take me to the darkest places imaginable. It was only fair then that sometimes I also allowed them to take me to a deranged fantasy land, where my mum had colour in her cheeks, and cancers shrivelled like old grapes. When everything goes to shit, thinking we can smell roses doesn’t make us stupid, it makes us human. Eleanor Margolis is a columnist for the i newspaper