I can kinda relate to your story. It's the biggest thing most guys struggle with including myself eventhough I've been getting alot more comfortable with talking to random girls. Taking that your good with befriended girls I'm asuming your a social guy with the lack of courage, like me.
On the other hand it's a good thing most guys have a hard time talking to girls they like, it makes the guys who can look good. And since you're here to improve yourself you'll soon be getting that advantage. I hope you realize that and it'll give you a boost when you want to talk to a girl you like.
What worked for me was: 'fuck it', try to care less and just go say hi to some random person. Like: 'hi, how are you doing?' then just cut off and go back to whatever you were doing. You actually talked to someone without any chance of failing or being blown off. While you continue to talk to random people (and not only cute girls), even if you only say hi and ask how they are, you keep building up more confidence. It's helped me to open up to people alot more and making me a more interesting person.
I wish you the best of luck and maybe I'll see you pop up sometime when I ask for help
