I might have PTSD and i really need HELP

I was in a relationship with a girl. We were engaged. She was my best friend for 4 years and after so many ups and downs we got in a relationship. But i was so blind in love that i didnt realise it was one sisded and one day she was gone unnoticed. It took me years to heal from that but after 3 years i met a girl she was sweet loving caring like everything i wanted from a partner. The girl of my dreams. So i thought of giving it a chance. It was long distance but we planned to meet eachother. Everything was going good. I used to stay in facetime , txt her good morning and good night txts. Used to motvate her. Used to send her flowers like a sweet lovestory yk!! But suddenly all started falling apart. All the things she said she loved about me she started getting irritated. She didnt respond to my txt that much used to say 1/2 hours per day is enough even tho its long distance and all i had is her presence. Like everything crashed downs and one day she left me saying she cheated on me and i cried my soul out coz i dreamt my entire life with her. I didnt wanna let her go. She hung up saying i dont have self respect. Days go by i try to suck it in but suddenly she txts me back saying she sorry. Rather resenting her. I felt bad for her. But it true that she is with someone else. Now whenever i try to sleep i hear her voice. I see the moment. I get nightmares of my oartner cheating on me. Some random dream when im being left alone in the dark being cheated on my heartrate starts spiking like crazy to the point i jump out of my sleep and i cant breathe and sweat like crazy. I cant sleep cant stop the voices in my head. All i cant think is this bad thing is gonna keep repeating itself. Pls i cant afford a therapist so i shared my story. Pls help me