
Queen Victoria lined up the much older Prince Christian of Schleswig-Holstein for Helena to marry. This caused bad feelings between the queen and the Princess of Wales, as well as the Prince of Wales and the queen's daughter Alice. Remember the Prussian wars to unify Germany and their war with Denmark and seizure of Schleswig-Holstein. Don't make me go through that again. Prince Christian didn't really have anything to be prince of, but he was willing to marry the ummmm dowdy Princess Helena and be kept by Queen Victoria, so the marriage was a go. In the end, they were devoted to one another.
"What shall I do with Christian now that I have him?" must have flitted briefly through the monarch's grieving consciousness from time to time. Queen Victoria's only goal was to have Helena stay close to her beck and call, and that necessitated a husband who had nothing to do and no land to rule.
The queen gave the newlyweds a gift of £100,000 plus she requested £6,000 a year from parliament for the couple, which she got, of course. Helena became the queen's sort of personal secretary. The queen made Christian the Ranger of Windsor Great Park, which came with a house to live in. Shades of Yogi Bear. The queen also made Christian High Steward of Windsor. Both positions were merely figurehead in nature, so Christian was left free to play with his dog Corrie and feed his numerous pigeons. That's about it. (Not to demean his manhood or anything.)
Helena and her younger sister Beatrice catered to the queen, with Beatrice being in charge and Helena doing what Beatrice didn't have time to do.
Helena was not in good health. Actually, she was in pretty good health (for her size) but was a hypochondriac. She was addicted to opium and laudanum. Queen Victoria didn't believe she was sick and said as much in letters to her other daughter Vicky in Prussia. To which Vicky replied... ah, well, who cares what Vicky thought, eh?

Besides needlepoint and serving meals to the poor (which made her very popular with the poor, but which I am going to gloss over in this account) she also liked to write, especially translations (German to English.) Perhaps her most famous translation was entitled, rather redundantly, "First Aid to the Injured."
In 1916, Helena and Christian celebrated their golden wedding anniversary. Despite the two countries being at war, German Kaiser Wilhelm II sent a congratulatory telegram to his aunt and uncle. George V was present when the telegram arrived and was not wholly amused. Christian died the next year. George V changed the family name to Windsor and disposed of all the British royal family's German titles. So Christian was just plain old Christian. They still called him prince up until his death, though.
Helena has been described as "...plump and dowdy... placid..." But also businesslike and authoritarian. Go figure.
Her daughter, Princess Marie Louise, described her as, "... very lovely, with wavy brown hair, a beautiful little straight nose, and lovely amber-coloured eyes... She was very talented: played the piano exquisitely, had a distinct gift for drawing and painting in water-colours... Her outstanding gift was loyalty to her friends... She was brilliantly clever, had a wonderful head for business..."
Helena was also fearfully devoted to The Queen - to the point where she did not have a mind of her own. But, in the end, her name was the last one written in the queen's 70-year-old diary before she died.
Helena herself died in 1923.