Recent months have revealed a new emotional terrain in my romantic relationship of the last 16 years

I've written previously about living in an open relationship with my partner Jo.

Jo was the first subject I thought to reflect on in writing about gratitude this month and now I want to share my gratitude for the growth spurned on by sleeping with another woman.

At Burning Seed last year I met a fun and thoughtful woman who interested me and seemed interested in me and one thing led to another.

Physical intimacy led to exchanging letters and it felt like I rediscovered the joys of writing and reading, particularly the pleasure in restraining from opening the envelope until the moment seems right to savour the contents without interruption.

It stirred me in a different way to how my primary partner stirs and we've spent many months trying to reconcile our feelings.

She would grow jealous at times, even times when I would be on Facebook and she'd observe my posture and know I was engaging with this other woman.

We've both agreed it has opened new aspects of ourselves, prompted by differing emotions and the dormant memories of infidelities.

During those months I was interested to read on Facebook the experiences of another friend who'd entered into a relationship with a couple.

She distinguished polyamory from polygamy, seperating the love of many from that of lovers who have entered into an exclusive relationship with each other.

It's led my partner to decide she'd prefer we agreed on sharing ourselves with someone, rather than watch each other find another person.

Now it feels like we're about to turn another corner in our relationship and I'm faced with finding a way to share this development with my onetime lover turned penpal.

I am grateful for the way she has enriched my primary relationship during times when she was seen as a threat to it.

She has opened new insights and prompted conversations that might not have happened otherwise.

It hasn't always been easy but it has been revealing and, like making up after arguing, reinforced our desire to be together.