Note: I messed around with canon a bit for this one.
"But what are you promising?"
"To always love you…"
"Blaine, tell me, are we really okay?" Kurt asked, terrified of the answer he could receive.
Blaine gently brushed Kurt's ever errant strand of hair out of his eyes and softly kissed his neck. Kurt was lying on his side on Blaine's bed curled up into a tight ball with Blaine pressed up closely behind him.
"Yeah, we're okay."
Kurt's sigh of relief was so big, Blaine could physically feel much of the stress leaving Kurt's body.
"Thank God," said Kurt. "I thought your distance lately meant you stopped loving me, and I really couldn't handle that."
"I am so sorry, Kurt. I never meant for you to think that at all. I guess I thought by pushing you away, I could make it hurt less for both of us when you leave Lima, but I was so wrong."
"I'm really sorry about the texts from Chandler, too. I hope you know they meant nothing to me. I asked him not to text me anymore."
"No, honey, I know they didn't. I'm sorry, too. If texts containing the world's worst pickup lines could make you feel good just because someone was paying attention to you, then obviously I've been a terrible boyfriend."
Kurt rolled over on the bed to face Blaine. "Don't say that, Blaine. You're an amazing boyfriend, and if you don't know that, then I'M sorry."
Blaine held up his hand to quiet Kurt. "I want you to always feel wanted. By me. It kills me to think that you thought I had stopped loving you. That couldn't be farther from the truth. I will always love you."
"Even when I'm an insensitive asshole and don't realize you're hurting, even when you're trying your damndest to hide it from me?"
"Yes."
"Even when I'm stupid and don't realize when another boy is hitting on me?"
"Of course."
"Even when I won't let you drive my car even though I trust you with my life?"
Blaine scrunched up his nose. "I still don't understand why you won't let ME, of all people, touch it, but yes, even then."
"Even if I throw away your hair gel?" Kurt teased.
"Weeellll…"
"Even if I donate ALL your bowties?"
"Shit, Kurt, I don't know… you know how much I love my bowties," Blaine joked right back.
Kurt fell silent, and Blaine sensed immediately that the mood had changed. He scrambled up into a sitting position at the head of his bed, leaning back against the headboard. Blaine urged Kurt to sit up and lay his head on his shoulder..
"But seriously, Kurt, I love you. No matter what happens, I never plan on stopping. And even if we were to ever move on from each other, which I'm telling you right now I will fight my ass off to prevent, I will still always love you. You never stop loving your first love. I will always honor you and treasure you and be at your side in the good times and the bad, as long as you'll let me."
Kurt grinned. "Those actually kind of sound like wedding vows."
Blaine reached down and grabbed Kurt's hands in his own.
"Some day, I hope they will be."