My gf is slowly turning into a slut and I love it

My girlfriend is a 22 year old sexy white girl. We have been dating for 2 years. A few months ago I came across cuckold stories and porn and turned me on so much imagining me and her in those situation. I wanted her to cuck me so bad. So I started to dirty talk to her whenever we had sex. I started asking about her previous sex experiences and so on. She was shy at first but then she started talking about it and she get the wettest whenever she talks about it. She told me about the story of how she lost her viriginity and it's the hottest story ever. She was 18 when it happened. She was shopping in a mall and she was approached by a 30 year old guy. He started talking to her for a while and got her number. Later that weekend he invited her to his place. She agreed and he picked her up. They went back to his place and got in his hot tub. After a while they went to the living room, dried themselves and got comfortable on the couch. He started rubbing against her and she was very wet at this point. He slid his hand under her panties and started fingering her. She was so turned on. After fingering her for a while, he took her to his room and layed her on the bed. He kissed her and layed his dick on her face. This is the first time she saw a dick in real life and she claimed that it was huge. She slowly started sucking it and then he fucked the shit out of her and finished inside her. They had sex 3 times that night. Hearing this turned me the fuck on and we have the best sex of my life that that. Recently she downloaded tinder upon my request to flirt with other men.