I had a very close friendship with someone, like the OP, but unfortunately it ended horribly. And if you do have feelings for Luan but she can't return them, I would advise you to move on. (Based on my experience) It was hard, but I wasted 6 months on something that I should've ended from the moment she rejected me. Your situation might be different from mine though.
My worst heartbreak would have to be with this girl named Erin. We were REALLY good friends for about a year. I met her from band. We did everything together with our group of friends each weekend from playing 007 Nightfire, watching movies, Brawl, Corn mazes, and random trips. Possibly twice in a weekend. Pretty soon, she grew on me. The only problem...I was 19 and she was 16...so I was really hesitant about starting a relationship. I was in very good standing with her parents. They really liked me. But I made sure we never hung out alone, because her parents might not take that well and I didn't know how they felt about that. We talked every single night through texting for an hour or two for about 3 to 4 months. The times and memories I had with her were honestly some of the best in my life.
After awhile, I just decided to tell her how I felt and see what she would say. She told me that she would get back to me because her dad might "have a heart attack." (about the 19 and 16 age gap) and that she was worried about splitting our friendship group up, and that she got screwed by guys in the past. But 2 days later, I got rejected. We hugged and I respected her wishes at the time,
saying we could still be friends.
And that was my biggest mistake.
For the next 6 months I was friends with her, but things weren't the same. We didn't talk every night and we just hung out every single weekend with our friends. The pain was definitely there. I missed the closeness we had before I told her. Soon enough, she asked me if our mutual friend at the time (a guy) could start hanging with us. I began to notice she started blanking out my end of the conversation and only listened and responded to this guy. I began to get jealous and the pain worsened, yet I kept it in. I dated other girls at the time, but nothing really happened.
Soon enough, summer rolled around (this last summer.) and I was still "in love" with her. I had to make a choice.
-Be her pussywhip/friend and hang out with her alot more now that school was over, watch her ask this guy out, and prove all her reasons for rejecting me wrong
-or end all communication completely with her.
After a long-ish convo with my best friend, I decided to end our friendship and communication with her through text. There was just no way to get her alone...maybe I could've done better here. She said, "What the hell, Louis? Why?"
and I told her how I dated other girls while being friends with her, but noone else stood out as much as her. And as long as she was my friend, there was no way I was going to get over her. She didn't say anything after that. And I deleted her from Facebook and all that jazz.
It was quite ugly afterward whenever we crossed paths irl. The first time I saw her again after that was terrible. She walked in with that guy to a graduation party and I just left immediately and sat on a swing at the nearby park (lolemo) When they all came outside, I left the swing and started throwing rocks in a nearby field as hard as I could. (lol)
And we haven't said a word to each other for nearly six months. I'm sticking to my guns. She's now (and currently) dating that guy. Called it from the 1st day she hung with him with me. A frickin' D&D nerd over an awesome guy like me. He's 18, which proves the stuff she told me about her dad was not true, and that she couldn't give a care about how her friends would feel.
Luckily, one of the other guys in my original friendship group is still really good friends with me.
**** happens I guess and I'm doing just fine today.

See her every once in awhile, but I continue to ignore her/be an *** on the exterior. Dated this one girl for a month (older than me. lol), but it didn't work out, but it happens. I still strongly dislike Erin so much yet I still kind of have a soft spot for her. >_>
Moral of the story: Never settle for friendship if you really "love" a girl. Don't kid yourself. You can't just go back to being friends and say you're over her just like that.