War is made of blood and terror, but it is also made of emotion, not all of it logical, easy, pretty or comfortable to express. In Ukraine, there is a “maelstrom of guilt”, the film-maker Iryna Tsilyk told a book festival audience in Lviv recently. “Each of us finds something to be guilty about … Those who left the country feel guilty for those who have stayed. Those who have stayed but live in the rear feel guilty for the military. The military have their own guilt – they feel guilty for their brothers and sisters who have had different levels of experience.”

There is survivor’s guilt when your fellow soldier was killed and you escaped unscathed. There is guilt for not “doing enough” to help the war effort. There is the guilt felt when your friend’s boyfriend is serving, but your own partner is exempt from mobilisation. Russia’s war has snatched territories from the Ukrainians, but has also insinuated itself into people’s relationships, where it squats, monstrously, between friends and lovers and family members.

These facts of war are difficult to express and reify. Art offers a route. The young Odesa-born artist Dasha Chechushkova has made etchings loosely based on Goya’s series Los Caprichos: lonely, delicately rendered figures are accompanied by texts that express guilt, alienation, anxiety, fear. “It is like a collection of symptoms and depressions,” she tells me, “thoughts that most of the time we can’t tell anyone: loneliness, strangeness and the distance between people, because we all had so many different experiences now.”

In Kyiv, the artist Bohdan Bunchak, a tall, slim, moustachioed man in his 20s, tells me about his own sense of guilt, and how he has expressed it through a remarkable 10-minute film work. In February 2022, he was a novice, preparing for life as a monk, in the far west of the country. War “grabbed me out of that monastery”, he said. Over the next year, he returned to his former life as an artist. And yet, “I had a big black hole in my conscience,” he says. He went to the draft office just after Easter 2023. By June he was in battle, near Lyman in Ukraine’s east. On his fourth assault, a month later, he barely escaped with his life.

What happened was this. One evening, he and his small squad, of which he was the leader, had just completed a mission in the Serebryansky forest. He got back to their base – cradling a badly wounded soldier who was thrashing and convulsing in pain all the way – at 11pm. He talked to family and friends on the phone until about 3.30am, bringing down the adrenaline, anticipating a few days’ rest. By the time he put his head down, still unwashed after the three-day task, the night sky was beginning to brighten into dawn.

The walkie-talkie call at 6.30am came as a shock. The position they had been defending had been lost. The order was to go straight back in and retake it. Somehow, Bunchak gathered his men, glugged some energy drinks, ate some Snickers bars. They were meant to make a joint assault with another team, but the others came under fire and never arrived. He was sharing a trench with two fellow soldiers and the corpse of another when he got word that help was on the way. He crawled out of the trench to inform the rest of his men – when the explosion came. A flash, smoke, a sound that knocked him off his feet – and no feeling in his lower body.

Bunchak was taken to hospital. Surgeons removed shrapnel from his spinal cord. Regaining movement in his legs was a long and painful process. Now, a year on, he can walk but still has little feeling in his lower limbs. Bunchak is now attending theological college, wondering whether life will take him towards the priesthood. He is also working in a programme to help reintegrate veterans into civilian life – and making art about the horrifying experiences of fighting in Russia’s bloody war.

Bunchak’s film You Ain’t Even Try – the title a reference to a Kendrick Lamar lyric – is a terrifying, 10-minute insight into the haunting feelings of guilt and responsibility that Bunchak feels after his No 2, on a earlier mission in the same forest, was killed by explosives let loose from a Russian drone.

The work is not graphic; there is no hint of the horror and indignity of the man’s death. Nothing could convey that, and no one should see it. Bunchak, when we speak, seems caught between the sense that his work is “not harsh enough”, does not go far enough in conveying the reality of the battlefield, and the knowledge that “a snuff video is not art”. An artwork, he says after a moment, can at least “trigger you to think about the harsh stuff, the horrible stuff, the terrifying stuff – in a safe way”.

You Ain’t Even Try is put together from found materials – film footage, computer graphics, animation. “You are a goddamn murderer,” repeats an AI-generated child’s voice over shots of forest and fields and a track of church bells. Watching it, you feel that you are disappearing into Bunchak’s psyche.

Bunchak blames himself for not having his first aid kit on him at the time of the attack, when he and his fellow soldier were carrying an ammunition box across an exposed area. But no first aid kit could have saved the man, whose bones and lungs were exposed by the blast.

“I feel guilty because I was in charge and I had the responsibility,” he says. It seems an awful, unfair burden to add to the sense of loss. (Of the 60-strong company of which Bunchak was part, 11 died. Of the rest, only five or six escaped without serious wounds.)

Towards the end of our conversation, my Ukrainian colleague Artem Mazhulin pitches in with a question, perhaps the obvious question. “Do you think the Russians feel guilt?” he asks Bunchak.

“I don’t think about the people in Russia,” replies Bunchak. “I think about all these people all around us, and what they feel. Because what they feel is the future of my country.”

• Charlotte Higgins is the Guardian’s chief culture writer