stuck at friends

So over the years I've been denied being more than friends with a few of my friends. I feel like I'm being denied a promotion. I don't understand how I could be friends with someone over the years and some guy comes along who they've either barely talked to, just met, met through a friend, or whatever and then start dating. Where I've known the girl for years and put aside. It's crazy how the guy then just learns all these things about my friend that I didn't even know. The worse part is when they tell me that they want to stay friends or don't want to 'loose you' as a friend.I don't understand this. Sometimes its hard working being friends but it's worth it all the time. It would be worth it more if the relationship went past the 'friend stage'. I'm starting to think that it's not possible to go past just being friends. I'm not the type of person to go out and find some random girl and date them without knowing them. I need to spend some time knowing them so this is why people become friends first. Maybe it's a waste of time trying to go past friends.