I(22m) am a newly-born father to a beautiful child but paternity is in question.

I(22m) am a newly-born father to a beautiful child but paternity is in question. My gf(21f) gave birth yesterday and I am overjoyed. But I just found out that there is a chance the baby girl is not mine. I am devastated and I don't know how to react.<br><br>I had been dating my gf for 7 years and we had been living together for a year. I trusted her completely and valued our relationship more than anything.<br><br>However, a week before my girlfriend's due date, she confessed that she had cheated on me last summer. She said that she had a one-night stand with someone she met at a party. I was devastated and couldn't believe what she was telling me.<br><br>I asked her if the baby was mine and she said yes, but I could see the uncertainty in her eyes. I decided to wait for the paternity test results before reacting.<br><br>The day before yesterday the test results came and they said there was a 0% chance I was the father. I was heartbroken and shattered into a million pieces. I felt as if my whole world had been turned upside down.<br><br>I didn't know how to react or what to do. I felt like I was living in a nightmare. I spent the rest of the day crying, calling my friends and family, and feeling helpless.<br><br>The next day I received a call from the hospital and was told that my gf had given birth. I went to the hospital and saw the baby girl and she was beautiful. I held her in my arms and felt a mix of emotions. <br><br>Even though the test results indicated that I wasn't the father, I still loved the baby as my own. However, the pain and betrayal I felt towards my gf were overwhelming me. I didn't know how to process my emotions or how to navigate this situation.<br><br>I want to do what's best for the baby but I'm struggling with my own feelings. I need advice.<br><br>What should I do in this situation? How do I cope with the pain and betrayal?<br><br>&#x200B;<br><br>Tldr: I am a newly-born father to a beautiful child but paternity is in question.