About 18 months ago, I had what I can only describe as a breakdown, caused by my OCD. Since then, I've worked my way up to the maximum dose of the anti-depressant sertraline and as a result gained three stone, completely lost touch with reality and almost entirely lost my spark. It's like I've been drained, like I'm not really me anymore.

Sertraline is used to treat depression, panic disorder, post-traumatic stress disorder and social anxiety disorder. In my case, it's used to treat OCD - specifically intrusive thoughts - which are almost always about my then partner, now wife.

After much consideration, I'd rather be a hazy, numb lump than bedridden and insane

The thoughts that tipped me over the edge ranged from a fear of her gruesome death envisaging her in a pool of blood after being knocked off her bike to a dread of potentially sabotaging our relationship myself this one was particularly bizarre and nonsensical . Being tipped over the edge involved me in bed for around a month, sweating, shaking and unable to eat or work - quite literally haunted by my thoughts. It was a living hell.

I spent another six months or so having cognitive behavioural therapy, on diazepam and gradually increasing my dose of sertraline. The past year has been breakdown free and for the most part anxiety free. The thoughts still bother me sadly, but I can handle them now.

Thanks in part to the therapy and greatly, I believe, to sertraline, I'm feeling a hell of a lot better and can work, eat and go about my daily chores successfully. And, after much consideration, I'd rather be a hazy, numb lump than bedridden and insane.

Millions who take anti-depressants regard them as lifesavers. I can see why

The weight gain has been incredibly frustrating - even more frustrating because my research shows that many people actually lose weight when they take sertraline. I'd rather be fat than mad though. And my wife is pleased - in her words, she gets more for her money.

The feeling of complete detachedness is depressing at best. I remember feeling more grounded before all of this, I recall feeling things more intensely and in all honesty, I remember being happier. It's a miserable void - I loved feeling stuff. But I'd rather this than lose my mind again.

See that's how dreadful OCD is - and indeed, other mental health issues. It's not being a bit tidy or checking the door excessively - it is a horrible and debilitating plague of the mind. Research often shows that anti-depressants give serious side effects, and yet millions who take them regard them as lifesavers. I can see why.