I didn’t realise it at the time, but I was already developing traits associated with borderline personality disorder (BPD). Everyone with BPD experiences it differently, of course, but I fluctuate between being in a really low mood, like a depressive state, and feeling really high, like I can take on the world. It’s exhausting because I can switch between these two states within a day, or even within an hour. I can feel intensely happy, but then something will trigger me and plunge me into a really low mood. According to recent research, 2.4% of people aged 16 to 64 in the UK have BPD.