Ernie had a really difficult life; losing his brother at that young age and feeling it was his fault, and then his little sister, and his mother caught diphtheria from him! If he was gay, which I think he probably was, he must have felt the isolation of having feelings many thought were "evil". Then his horrid marriage with Ducky, and the death of dear little Ella, who was so close to him.
Even for the times, his was a tragic lot. At least Queen Victoria's children didn't have to lose both a parent and two siblings at such a young age. He seems to have been exceptionally kind and loving to all his sisters, children, and nieces and nephews.
No wonder so many people of Hesse grieved deeply for Elisabeth! All of Alice's children had warm, glowing hearts, and little Ella (despite being a bit spoiled, perhaps) must have been a jewel of a child.