Rodolphus remained in the study long after Bellatrix left, this was the happiest he had been in 13 years. They had always had a very strange relationship, he knew that everyone thought he was crazy for staying married to someone who very clearly did not share the same feelings, but he did not care. None of that matter to him. Ever since they were at Hogwarts together Rodolphus had been head over heels for her, even though she never paid him much mind, there was just something about her.
The two of them hung out with the same group of kids back then, most of whom became death eaters with them, but that was about as close to Bella as he got. He had asked her out once in their 7th year but she turned him down. That far from discouraged his feelings for her, he decided to just bide his time. She was the most beautiful witch he had ever laid eyes on, she had classic good looks without even trying.
Back then her hair while still long and curly, was a smooth rich brown. Her eyes were the deepest brown he had ever seen and while still large, did not hold the madness and bloodlust that they do now.
Bellatrix was never really sane, her madness was degenerative and was not very noticeable until after they left school. Anyone who was not close to her would have had no idea of the insanity that lay just below the surface, but those who knew her knew the madness within. Rodolphus loved her madness and her passion, he had never met anyone like her and knew he never would.
She was one of the top students in her year, without even trying, and things she cared about she did with all of her heart. Mind you, most of the things she cared about were: causing trouble, practicing dark magic in abandoned classrooms, and jinxing first-year students. It is not hard to see how she ended up where she did.
After they left Hogwarts Bella's family approached his about marriage, Rodolphus was thrilled with the idea but it was clear that Bellatrix could absolutely care less. Always rather positive he knew it could be worse, at least, she did not hate him. After a while, they came to an understanding and wed shortly after. They were married for less than a year before they were recruited as death eaters. That is when he lost all hope of her ever returning his feelings.
If he had not been so passionate about what they were doing he might have protested but he knew that this was what she wanted and he only wanted to make her happy. Voldemort had seen a lot of the same things that Rodolphus had from the very beginning. Her passion and skill set her apart from the other death eaters and she was taken under the Dark Lords wing. As soon as they were recruited it was clear that Bellatrix favored Voldemort over Rodolphus and it did not take long for her to fall completely head over heels for him.
They worked extremely well together and as Bellatrix rose in the ranks so did Rodolphus. Despite how she felt about him she kept him by her side, and after all the years he would almost say that they were dear friends – almost. If they did not have the same name you would never know that they were married as Bellatrix never spoke of him. Their relationship was a working relationship and that was it.
When they first got married he hoped that one day she would come to love him, when it was clear that was never an option he was happy with what he could get. Rodolphus was to Bellatrix as Bellatrix was to Voldemort though he sometimes had a feeling that Voldemort cared more about Bellatrix than she cared about him. It was okay, though, he was happy to be there with her. He was like her shadow in battle, never far away and always there to protect her if she ever needed such a thing.
After training with the Dark Lord her already great dueling skills were outstanding and so he would not embarrass her she started training with him. He absolutely loved it, it was the best part of their relationship. He cherished all the time she allowed him to be with her and loved seeing how passionate she was. It was how he fell in love with her and continued to love her after everything they had been through. While he would always hope that things might change, although fairly certain they would not, he would rather have her like this than not at all.
It was not long before he found himself back in his room. He fell asleep dreaming about the next time he would get to train with her. He slept the best he had in 13 years, happy to have his wife in the small ways she allowed.