Regulus POV
Lily was a bitch. No, she wasn't. Regulus really needed to stop thinking that Lily was a bitch. She was nice and smart and James really liked her. And calling her a bitch was misogynistic and bad. James was with Lily who was smart, beautiful, and James loved her. James loved her. James loved her and Regulus was okay. His okayness did not depend on who James loved. He was fine. Completely and utterly fine.
He was so fine that ever since James had started dating Lily, Sirius had started calling him every day to check up on him. The best part of having a sibling is that one moment they can be a total asshat rat, and the next moment they do the sweetest thing. Regulus hadn’t been this grateful for his brother since they were little and Sirius would take the blame for him whenever he got in trouble.
Sirius knew that Regulus was in love with James. Regulus had never had to tell him, he just knew it. Before James had started dating James, he would pester Regulus into asking James out, but Regulus always denied his request. He knew that James didn’t feel the same, and he didn’t want to ruin their relationship by making it weird. Now James was happy and with Lily. Which was great, and Regulus was totally fine.
There was a knock on the door, "Reg," James called through it.
"Coming." He said as he got up, still in his pajamas, and opened the door.
"Want to come to a party tonight?" James said with a weak smile. In that moment there was nothing Regulus wanted to do more than make his smile real, the classic luminescent James smile.
"Um, sure." He said then paused. "Is Lily coming?" Regulus wasn't sure she could muscle through another night of being a third wheel to Lily and James, or Jily, which was the name Lily's friends gave the perfect couple. Hearing that name always made him want to vomit. Preferably on one of Lily’s friends.
"No." He sighed, "She had to meet with her friend Mary to study. So I need someone to come with me." That's great. Regulus fucking loved being James's backup date. Maybe it wasn’t fair, but James used to call him whenever he wanted to do something, now Regulus was just a backup date. He wasn't even his date, James would have had to see him as anything romantic to be a date. He was just his whatever. The person he called to hang out with when the person he really wanted to hang out with was busy. But Regulus was okay. Everything was fine.
“Yeah, sure. I’d love to come.” Regulus couldn’t do anything but agree. Part of him wanted to say no. He wanted to tell James that he needed to find someone else to hang out. Regulus wasn’t a backup plan or just his bro that he could hang out when his girlfriend was busy. However, Regulus couldn’t manage that. He would do anything that James asked him to. Regulus has never turned down spending time with James and he didn’t think he would ever be able to. Which is perfectly fine. Regulus was completely okay.
"Great" James breathed. "So we can leave when you are finished getting ready."
"What, this isn't a fancy enough outfit for you?" Regulus said as he smoothed his t-shirt and pajama pants. He was fully capable of being normal and joking with James because everything was fine.
"If you want to wear that go for it." He smiled softly, "You'll still be prettier than everyone there." God. Regulus should hate him. He should want to punch him in his stupid perfect face. He really should. James has the audacity to say stuff like that to him when Regulus can't have him. Because he's Lily's and they are in love. Tonight after this party, he is going to go home and sleep in a bed with Lily. He may think Regulus is the prettiest person at the party but he is still going to go home to Lily. And Regulus was completely okay.
"I'm going to go change." Regulus turned quickly as he felt his eyes start to water. He couldn't cry, he was better than this. Lily and James had been together for over a year now, he couldn't still be crying over this. James loved Lily, he should be happy for him. And Regulus was so okay.
After Regulus put on his button-up ship which he tucked into his slacks and fixed his hair and makeup, he walked back out to his living room where James was standing staring at the wall with a weird look on his face. It was some kind of sad, not like after his dad had died but more of a given-up sad. Regulus hated it. More than anything he needed James to be okay
"You ready?" James said looking up at him.
"Yeah," Regulus breathed.
James paused looking at him for a few seconds. He could feel his eyes burn into his skin, "Are you okay?" James asked seriously.
"I'm fine," Regulus answered. Because he was fine. He had no reason not to be fine, and even if he wasn't actually fine, which he was, telling James that he was fine was the only answer he could actually muster. "Are you okay?" Regulus asked because based on the look on James’ face, he wasn’t sure.
James took a shallow breath and said, "I'm fine." If James's fine was anything like Regulus's fine, then he wasn't okay. James had to be okay. Regulus could deal with being sad if it meant that James was okay. He didn't have any reason not to be okay, he was at the top of his class in med school, and he had a beautiful girlfriend, which he went to school with along with his best friend. James had to be okay, he should be happy. And Regulus was okay. "Let's go."
Once Regulus came back home alone to his apartment, he called Sirius, “I don’t think I’m okay,” Regulus sobbed.