So I've been dating this girl for a while now. It started great but by the third day, things went downhill. She won't reply to my texts, or calls. So today I found out that she left for Christmas vacation to another country this morning. It's like "hello? we're in a relationship. Shouldn't we at least tell each other when one is leaving far away for a long time?" Should I break up with her or not because it does not seem that she wants the relationship to survive?

How long have you been dating? Because it sounds like three days. Maybe you can clairify. Also, define what you think a relationship is. This would be helpful.
Does she feel the same way you feel about her?
One last Question... What are your ages?

https://www.askmehelpdesk.com/teens/ex-girl-accused-me-cheating-didnt-heart-broken-424137.html

Your 13 going on 14,I understand that you say you love trisha,but maybe she wants some freedom,maybe she feels now after 2 years that things are too serious and she wants to break up,but does not know how to tell you.

She has already accused you of cheating,which you say you did not do..

Even though its hard to get your head around,maybe its time to move on.

There are so many girls out there,and so many things you can do,hang out with your friends,play sports,school...

Give yourself time to mature more and you will get the tools you need to develop a relationship in time.