Retroactive jealousy: Obsessed with my partner’s past

Zachary Stockill's obsessive thoughts about his partner's previous sexual experiences led to the collapse of his first serious relationship. It took time for him to discover that his problem had a name - and that thousands of other people also suffer from it.

I was in my early 20s and, for the first time, I was in love.

One evening my girlfriend and I did what a lot of new couples do at the beginning of a relationship - we started talking about our pasts. The conversation moved on to previous relationships we'd both had.

A switch flicked in my brain.

There was absolutely nothing she said that was out of the ordinary, no details that were particularly unusual, shocking or even titillating. But something changed.

Her romantic history was suddenly all I could think about.

I grew up in a small town in northern Ontario, Canada. My parents had an excellent marriage and for the most part I had a great relationship with them. I didn't grow up with mental health challenges - no depression, no anxiety, no obsessive compulsive disorder (OCD).