When you’re happy and in love, the sensation that produces is arguably one of the most joyous in existence. Buoyant and invigorating, fortifying and reassuring, it wraps life with a sense of can-do that’s intricately linked to your partner and everything you feel about that person. You’re in this together; it’s the two of you taking on the world.

But when you’re in a relationship beset by depression, the sensation can be much different.  Often, it’s dark, heavy, and cheerless with everything subject to shift—be it a sudden slide or a slow and eventual drift. You might be together, but the depressed person often suffers from a sense of isolation—which in turn causes their partner to feel alone as well.

It’s different for each person, of course, but when I’m in the throes of depression, it’s as though I’ve sunk to the bottom of the sea. Often, I arrive there without warning, resting on the ocean floor, staring up the bobbing legs and arms that break the surface above while I’m drowning, weighted down by inertia and a heart as leaden as a brick.

The last time I sunk into a depression was one of the worst so far. My mother had recently died and although I’d spent much time grieving, there are only so many emotions one can process at a time. Too often life gets in the way of really moving through the many stages of loss. My job was intensely busy and I felt content to bury myself in hours of work. Sometimes though, when I took a moment to breathe, I found myself struck with a profound sense of emptiness.  

My work felt flat, unsatisfying. Life seemed meaningless. So many of my usual interests and hobbies felt pointless and without purpose, while many of my friendships seemed fleeting—frustratingly void of meaningful connections. It’s difficult when you’re in your forties and your friends also have intense jobs and families and packed schedules that don’t leave room for much else.

And then there was life with my husband. What is it that they say about hurting the one you love most? It may not be intentional, but when you live under the same roof, it’s damn near impossible to not be affected by the other’s mood, good or bad. Just as a partner’s joy or optimism can elevate the relationship, my sadness and sense of futility can threaten to take my husband and my marriage down with me.

That’s how it seemed on the eve of my last birthday. I felt spent, as if every cell in my body ached. The sense of futility had been simmering for weeks but, mostly, I’d been too busy to deal with it, trying to ignore the warning signs. But there it was now, crushing in its hold as I tried to mentally prepare for the ceremonial passing of another year. Instead of viewing it with optimism—I was physically healthy! There were still so many opportunities to be had!—I stared it down darkly. Years were ticking away with increasing speed. I was over, I was finished, I had little left to give.

What fun, right? No wonder my husband’s initial reaction was one of barely stifled exasperation. It was my birthday, and he wanted to celebrate it. He wanted me to be happy and at least try to find some joy.

I can understand his frustration. I’ve been on the other side of depression, too, and it makes you feel helpless. In the past, I’ve watched as my husband became overwhelmed by life or a sense of misdirection. I’ve heard well-meaning but unhelpful things come out of my mouth—“You have to move on,” “It’s not that bad,” “It’ll be fine”—as I’ve sensed him slipping deeper into the hole.

Whatever side you’re on, it’s an awful place to be. But over the years I’ve also learned it’s a place of growth and strength. Every time we have pushed through a wrenching storm of depression, we’ve emerged weathered but more determined, exhausted but somehow re-energized with a sense of purpose, too.

Scientists have studied the effects of depression and other mental illnesses on relationships. One qualitative study had unexpectedly heartening findings. In Their Own Words: How Clinical Depression Affects Romantic Relationships, published in the Journal of Social and Personal Relationship, examined partnerships in which one or both people suffered from some degree of clinical depression. Researchers asked each person to share his or her experiences of living in a relationship marked by depression.

The findings were revelatory. In addition to exploring the challenges of coping with depression, the respondents—135 couples in all—expressed feelings of empathy and connection. They spoke of a deep-seated need to help and, if they couldn’t do that in tangible ways, to at least serve as a rock, a guidepost, a lighthouse to shore.

Over the years my husband and I have tried to tap deeper into this empathy. We talk about triggers and how to recognize cues for help on both edges of the divide. We remind ourselves that neither of us is ever alone. We remind ourselves of the power of listening without judgment, and that sometimes just being there without words can be enough.

Without excavating every sad and ugly detail from that night before my birthday, I can share what I remember most from it. Me, lying on my side in bed staring at the wall as my husband rubbed my back, talking softly. Reminding me that I was not alone, that I had worth, and that he loved me. Then, as he so often does, he served as my anchor, a pull to the other side. That rock, that guidepost, that lighthouse to shore.

Rachel Leibrock is a writer and editor living in Northern California.