Svitlana Povar knew her husband would not approve when she enlisted in Ukraine's military and deployed to the embattled Donetsk region, where fighting with Russian forces is fiercest.

The couple -- together for some 20 years -- had made an agreement when the Kremlin launched its war in February 2022.

She would stay away from the front with their teenage son. He would fight so their child could one day live in peace.

But when Svitlana, 42, learnt on her birthday last September that her husband had been killed in battle, she no longer felt bound by their pact.

"I spent five months begging at the doorsteps of military enlistment offices," she recounted, her hands clasped tightly together, staring out the window of her Soviet-era flat on a recent rotation in Kyiv.

She described tearfully to AFP the heated debates she had with her husband, Semen, who was 38 when he was killed around Vugledar, but believes he would have come around to her decision.

"There are times when I feel that someone is watching over me. I tell myself that he's with me, that he's helping me," she said of her experience being deployed near the eastern city of Bakhmut.

- 'We have to end it' -

Semen's death and Svitlana's enlistment point to the fighting's huge cost for Ukrainians and the lengths to which women are going to aid the war effort -- even at the risk of orphaning their children.

Ganna Malyar, a deputy Ukraine defence minister, says there are 42,000 women serving in the armed forces, including 5,000 on the front line.

There are no figures specifying how many joined after -- or because -- their partners were killed on the front lines.

Svitlana choked back tears while she described her husband as a larger-than-life character who had joked on their very first date walking through a park that they would get married.

The desire to fight Russia's invasion was not driven by a need to take revenge, she explained, but rather the need to finish what he started.

"My husband used to say that we have to pass on our faith in God, love for country, the gift of mercy -- and not war. We have to end it, not our children," she said.

Yet Svitlana did not tell her son she was going to Donetsk -- the same region where his father, a sniper, was killed. She didn't know how to tell him.

- Prepare for war -

But while he was studying in Poland, he drew the conclusion himself and has since tried to discuss with her what to do if -- like his father -- his mother is killed by Russian forces.

"When he starts -- maybe I'm wrong -- I cut off these conversations and tell him that everything will be fine, and that's it."

Yevgeniya Kolesnichenko, from the destroyed Donetsk region town of Avdiivka, decided at her husband's funeral to make good a long-held wish to become a frontline medic.

The 34-year-old was already in Poland with her daughter, 13, and 10-year-old twin boys when she got the call that he had been killed in Bakhmut in November.

His parents could not attend the funeral because they have been living under Russian occupation for nearly a decade in Donetsk city.

"When he died, I realised that someone needed to take up his cause," she told AFP, knowing that he would not want her anywhere near the front.

"People who are not fighting now should also, little by little, prepare for war. Sooner or later, most of us will be involved," she told AFP.

Does she sometimes think, since she trained as a medic in December, that she could have saved him if she had been there in Bakhmut?

"I know his injuries meant that he wouldn't survive. But now I'm doing my best to save other heroes," she said, the hum of bees mingling with the thumps of shelling around Karlivka near the front line in Donetsk.

"I work with the mantra 'so that as many husbands and sons as possible return home'. I'm always thinking that there's someone waiting for him."

- Death a 'sacrifice' -

Before the war, Yevgeniya -- the sides of her head shaved with her dyed fringe falling over her animated face -- had her own business designing cross-stitch and embroidery patterns.

She now works alongside two Ukrainian women who lost their husbands to Russia's invasion and knows several others, who, like Svitlana, serve on the front.

"Some have been so affected by the death of their men that they too join the army in one capacity or another," she explained.

Yevgeniya is clear-eyed about the possibility of her own death and has made arrangements with friends to care for her children if she is killed.

But she is still coming to terms with the loss of her husband.

"If you look at it from an emotional standpoint, probably no-one is willing to pay this price," she said of her husband's death.

But pausing for a moment -- as the sound of shelling carried over a nearby lake -- she explained that the fate of the country was hanging in the balance.

"That's why I'm here now. And I could die too. It would be my sacrifice. If everyone thinks it's not worth it, then it wasn't worth it to begin with."

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