Overthinking, relationships, miscommunication and overanalysation

i recently got back from a trip with my girlfriend for a night away, and since we've come back i think things seem weird, but according to my girlfriend things are okay. she thinks im worrying over nothing as we arent talking as much as we used to however this could be down to her being very busy at work. What makes this problem worse is that shes going away to work in Greece until november so i wont see her. How do i stop overthinking things and over analysing whats happening.

If your instinct is telling you something's not right, listen to it. Your relationship is about to go long distance and will a the test. Your GF's thoughts are not with you at the moment..she's thinking about Greece. She's mentally and unwittingly pushing you away. She needs to prepare herself to succeed at working overseas. You've identified the problem (things are weird) but she's too close to see it at the moment because her priority is elsewhere. Talk to her to get to her focus on her relationship with you, but ultimately, it'll be her actions (and yours) in the next 6 months or so, that will tell you if your weird feeling is justified.