Me and my gf are in relationship for around 4 months and have been talking for around a year. Yesterday, we decided to step up and have sex while being a bit drunk. Around an hour or so later, she called out name of her best friend.
Context:
My gf used to have a male best friend that was always there for her during her hard time, post the breakup of her last relationship, which went for around 5-6 months. He liked my gf and they used to spend a lot of time together, almost like the whole day and went their seperate homes in night.
I met her after that period and we started liking each other. Ofcourse, I confronted her and asked her if she liked her best friend to which she denied straight up and said that its not the case at all, and yet they would spend the whole day together. I had problems at the start (because I was kind of insecure at that time) but she assured me multiple times that she never liked him.
Recently, she forgot to reply him back and even call him back multiple times during his hard phase, which made him cut all connections with her. She confronted, they had a talk regarding it and decided to move on in their lives.
Now, coming back to yesterday. She called out his name twice while having sex with me. First time she blurted out his surname but stopped half way. I figured it out because his surname was very unique, but still I didn't put much thought into it. Then after a few seconds, she clearly called out his first name. I got hurt, stopped, cleaned myself and dressed up. As soon as I stepped out of the bathroom, I found her crying. I was ready to leave at that moment itself, but she was naked and I just couldn't. As I was dressing her up, she started crying and repeated that there's nothing like that and I don't know how it happened.
As we were drunk, I said, lets sleep and we'll talk in the morning. She continously cried and slept on the floor. I brought her blanket and pillow and I went to sleep on bed as I couldn't leave her in that state.
In the morning, I felt as if I'm dead inside. I couldn't feel hurt, disappointed, or anything. Its just blank. She said sorry multiple times, asking how could she fix this, and again reassured that there's nothing like this between them while saying that she doesn't know how it happened as she was drunk and was in a half asleep state. But I couldn't reply anything.
What should I do?
Update:
We sat and talked about it for more than an hour. I politely said that we'll go ahead with the breakup. To which she said that let's give each other time to think over it. (Ofc these are not the exact details but this is what happened in brief. It'll be either breakup or building trust and relationship from scratch)
So, basically the thinking period is going on.
And, I noticed some of you guys said that she's still in contact with her male best friend. I can confirm, she has not been for months.