Is it normal to like someone for 7 years?

I've liked this one guy (my ex-bestfriends brother, surprisingly) since 3rd/4th grade. I'm not completely sure when I started to like him, but I haven't been able to stop my feelings.

Now, if you're asking if I've confessed to him, yes I have. Once when I was "drunk". I could immediately see that he did not care about what I said(not sure if it was because he doesn't like me or if he won't listen to drunk people).

I've dated a few people already and he has had his first girlfriend too. All my exes were great, they were kinda nice and all, but I haven't been able to get him out of my head. I've never not thought about him. Not even a week goes by and I once again find myself thinking about him. I still remember me, my ex-bff and him hanging out together. We've played video games together, watched movies, swam and spent a lot of time just sitting on their floor doing nothing. It was so comfortable as if I really didn't care how he saw me. I accepted that yes, he was really annoying at times. He's a real snob, but I just can't help seeing him as an amazing person.

My ex-bestfriend knew about me liking him since about 5th grade so she tried making things happen as she wanted her brother to be happy and knew I could possibly give that happiness to him. I was a coward then and still am today. I really can't get myself to tell him how I feel. I don't even see him everyday even though we're in the same school, but whenever I do, I feel my heart actually stopping. It feels like I can't breathe properly and when he passes by me in the stairs I make sure to look back not so obviously just to see him happy talking with his friend about whatever they were talking about.

We had this one course together a few weeks back and I caught him looking at me a few times which of course got me excited. I felt like things were about to get better, like he'd finalky send me a message or something. But then one day I walked into the library and saw him with some girl. It was just like in a drama or something now that I think about it... He was sitting next to the girl as their school books or something were placed onto the table. They were laughing and being real close to each other, smiling. I approached the end of the bookcase searching for a book that I was supposed to read for class. As I got to the end searching by the author's name, I noticed him. By some chance he turned his sight and made direct eye contact with me. His companion didn't notice me and I turned my face back to the bookcase embarrassed. I pretended to quickly look through the books but obviously didn't even look at the names. I rushed away from the building and went directly home(without the book i actually needed). I don't know why though. I guess I was a little angry maybe? Perhaps just shy. I really don't know what it was that just washed through me when we I saw him. He still hasn't messaged me about anything.

We haven't actually really talked in a few years. I've been thinking about asking his sister if he's still single. I assume he's not, but I still feel like trying and I don't know why. I guess I just feel like I need to tell him he's kept my heart and mind in his hands for 7-8ish years now already.

So... Is it normal to be in love with someone for over 7 years?