It still hurt a bit. Seeing them together, seeing the way he looked at him with such unconditioned adoration, Sebastian couldn’t help but feeling a bit hurt at that. But it was good. He did not feel betrayed or jealous, just a bit nostalgic. Seeing them now, was showing him, what he could have had, if he hadn’t chosen the path he took. But he had. He had chosen his duties for the Chantry over his own love and desires. He had been the one to leave Cullen behind. And althought it stings a bit, seeing him with a new love, it stung much more watching him working himself into a wreck all alone with nobody to lean on when the burdens got too heavy to bear. It wasn’t as if he hadn’t wanted to reach out, to be the one to lift his burdens a bit. But it would have been only cruel on Cullen. So, he kept away. And then came Dorian and suddenly Sebastian got to watch Cullen bloom again. At first, he was jealous, verily so. But the moment he saw how easily Cullen could laugh in Dorian’s presence, how he looked at that foreign man with shining eyes and a happy, silly grin practically plastered onto his face, his jealousy burnt down pretty fast.
When Sebastian and Cullen got together back in Kirkwall, Cullen had been under a lot of stress and Sebastian’s demanding, youthfully uncompromising way of courting the Knight-Captain wasn’t exactly helping him relax. Seeing the man smile, had been a rare achievement for the brother. And now it was as if Cullen never stopped smiling at all as soon as Dorian was around. Yes, it still stung, but it was outdone by the warmth that spread in Sebastian’s chest whenever he saw the Commander of the Inquisition’s forces smile warmly at his new lover.
When the new Divine officially declared that marriage was a Maker’s blessing for all kinds of couples, finally allowing same-sex couples to be married under the Maker’s light, Sebastian knew Cullen wouldn’t hesitate to ask for Dorian’s hand. Unfortunately, the brother hadn’t been around to see it, but he had heard Varrics probably slightly exaggerated stories about it and he had smiled at that, or - to quote the dwarf on that - he had been glowing like the Maker’s bloody light itself was shining from his face. Of course Sebastian just had to offer his services for the marriage. Cullen had been stunned by the offer, to say the least, but to Sebastian’s great relieve he had accepted it. Dorian had been more concerned about it. He had sought out the brother in a quiet moment, asking if this was truly alright for him. He knew of the shared history between him and Cullen. They had talked long and some tears might have been shed as well, but eventually Sebastian could convince Dorian that he wanted this marriage just as much as Cullen and Dorian did. They had bonded over their mutual love for the man. Dorian had promised to try and make Cullen happy and Sebastian had said, that he never doubted that he would. This was after all why Dorian was best for Cullen, not Sebastian.
But that was all in the past now. As Sebastian put on his sacred robes he spoke the prayers with light in his heart. When he saw Cullen smiling nervously at him infront of Andraste’s golden statue, Sebastian met his smile with his own brilliant one. When he heard Cullen’s breath hitch in his throat, as his eyes fell on his gorgous soon-to-be-husband, Sebastian’s cheeks began to sting slightly from how brightly he was smiling and his chest swell with a warmth that spread there. When Sebastian spoke the rites as the lovers glanced at each other with pure adoration, he almost choked on the warm feeling of awe that overcame him. Just like Dorian almost choked on his tears of joy, when he finally spoke those two words, that would finally bind him to Cullen in marriage.
As Cullen pulled Dorian into his arms, to seal the marriage with a kiss, Sebastian spoke the Maker’s blessing on the couple and it was heartfelt.