They don't really sound like friends to me if they abandoned you when you needed them most tbh. I've had people do the same thing to me. You're there for them but the moment things get bad for you, gone. Crickets. Bye. Those sort of people aren't really your friends. You deserve real friends. I wouldn't say there's anything wrong with you to have this fear as lots of people have the fear of rejection. It's just not letting it continue to prevent you from getting the things you want in life. Like making friends. Maybe someone will reach out to you first. Or you may need to do the reaching out first yourself. It may feel like you can't overcome this now but that doesn't mean you won't ever overcome this. Hopefully that day comes sooner than later.