Thanks for bringing your concern here to PC, Rumble... and welcome to Psych Central. Since you're a teen one additional forum, here on PC, that may be of interest to you would be the teens' lounge (no adults allowed!) Here's a link:

https://forums.psychcentral.com/teens-lounge/

You may also find the school & study issues forum to be of interest:

https://forums.psychcentral.com/scho...-study-issues/

I don't know as I am the best member, here on PC, to offer you advice regarding your relationship experience since I'm a "senior citizen", as they like to refer to us. Personally I think at your age the type of thing you've experienced is simply the way relationships have a way of going. (I could tell you stories... but I'll spare you that.)

My thinking, with regard to the experience you describe is that you simply need to get out there & give relationships another go whenever the next opportunity arises. Will the next one you have turn out badly too? Yes, I'd say at your age that's probably likely. But, at least from my experience that's the way these sorts of things tend to go. Eventually it's likely you'll meet someone with whom you'll develop a more lasting bond.

You asked about how to get over the fear you now have as a result of your previous relationship experience. Here are links to 5 articles, from Psych Central's archives, that discuss how to overcome fear:

Act to Overcome Fear

How to Keep Fear from Stealing Your Life

How to Overcome Relationship Fears BEFORE They Take Control

https://psychcentral.com/blog/5-mind...dium=popular17

https://psychcentral.com/lib/overcom...king-mistakes/

I hope you find PC to be of benefit.