My girlfriend released my dog while I was gone

My (m23) girlfriend (f22) of 4 years released my dog while I was on a one week business trip in Europe. On the 5th day of my business trip my girlfriend called me saying someone opened the yard gate and the dog ran away. I was devastated as I had the dog for 5 years since he was a puppy. I was so in shock and upset and I’ve had more than one person asked me if something was up because I couldn’t stop thinking about my dog and looking depressed. I asked my girlfriend to put up lost dog signs with his picture and a 3000 dollar reward. When I came back my dog was still gone and I was thinking he was dead the whole time. 2 days after I came back I get a call saying they found my dog and I was very excited and my girlfriend said she was happy too but I knew that something was up when the vet that called me was 50 miles away. I drove up with my girlfriend and the vet said some old lady and her son found my dog on a trail and brought it to the vet. On the ride back I was very suspicious of my girlfriend and accused her of releasing my dog and she kept saying she didn’t and some people probably stole it and released it. She eventually starts crying and admits to driving up and releasing my dog. I’m angry at her and tell her how what she did was cruel and I said I’m probably going to break up with her because she could have gotten my dog killed, especially because he is a Shiba inu and looks like a coyote. She then accuses me of giving the dog too much attention and not her but I tell her if that was such a problem she was free to leave without releasing my dog. I dropped her off and drove straight to a hotel that allows dogs with my dog and stopped responding to my girlfriend even though she keeps blowing up my phone and is trying to call me. I’m too much in shock to make any rational decision at this point because someone I loved for 4 years betrayed me terribly